*/
/*
* Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2011, 2014 by Delphix. All rights reserved.
+ * Copyright (c) 2011, 2016 by Delphix. All rights reserved.
* Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
*/
#define WITH_DF_BLOCK_ALLOCATOR
-/*
- * Allow allocations to switch to gang blocks quickly. We do this to
- * avoid having to load lots of space_maps in a given txg. There are,
- * however, some cases where we want to avoid "fast" ganging and instead
- * we want to do an exhaustive search of all metaslabs on this device.
- * Currently we don't allow any gang, slog, or dump device related allocations
- * to "fast" gang.
- */
-#define CAN_FASTGANG(flags) \
- (!((flags) & (METASLAB_GANG_CHILD | METASLAB_GANG_HEADER | \
- METASLAB_GANG_AVOID)))
-
-#define METASLAB_WEIGHT_PRIMARY (1ULL << 63)
-#define METASLAB_WEIGHT_SECONDARY (1ULL << 62)
-#define METASLAB_ACTIVE_MASK \
- (METASLAB_WEIGHT_PRIMARY | METASLAB_WEIGHT_SECONDARY)
+#define GANG_ALLOCATION(flags) \
+ ((flags) & (METASLAB_GANG_CHILD | METASLAB_GANG_HEADER))
/*
* Metaslab granularity, in bytes. This is roughly similar to what would be
/*
* The in-core space map representation is more compact than its on-disk form.
* The zfs_condense_pct determines how much more compact the in-core
- * space_map representation must be before we compact it on-disk.
+ * space map representation must be before we compact it on-disk.
* Values should be greater than or equal to 100.
*/
int zfs_condense_pct = 200;
* an allocation of this size then it switches to using more
* aggressive strategy (i.e search by size rather than offset).
*/
-uint64_t metaslab_df_alloc_threshold = SPA_MAXBLOCKSIZE;
+uint64_t metaslab_df_alloc_threshold = SPA_OLD_MAXBLOCKSIZE;
/*
* The minimum free space, in percent, which must be available
* in a space map to continue allocations in a first-fit fashion.
- * Once the space_map's free space drops below this level we dynamically
+ * Once the space map's free space drops below this level we dynamically
* switch to using best-fit allocations.
*/
int metaslab_df_free_pct = 4;
*/
int metaslab_bias_enabled = B_TRUE;
-static uint64_t metaslab_fragmentation(metaslab_t *);
+
+/*
+ * Enable/disable segment-based metaslab selection.
+ */
+int zfs_metaslab_segment_weight_enabled = B_TRUE;
+
+/*
+ * When using segment-based metaslab selection, we will continue
+ * allocating from the active metaslab until we have exhausted
+ * zfs_metaslab_switch_threshold of its buckets.
+ */
+int zfs_metaslab_switch_threshold = 2;
+
+/*
+ * Internal switch to enable/disable the metaslab allocation tracing
+ * facility.
+ */
+#ifdef _METASLAB_TRACING
+boolean_t metaslab_trace_enabled = B_TRUE;
+#endif
+
+/*
+ * Maximum entries that the metaslab allocation tracing facility will keep
+ * in a given list when running in non-debug mode. We limit the number
+ * of entries in non-debug mode to prevent us from using up too much memory.
+ * The limit should be sufficiently large that we don't expect any allocation
+ * to every exceed this value. In debug mode, the system will panic if this
+ * limit is ever reached allowing for further investigation.
+ */
+#ifdef _METASLAB_TRACING
+uint64_t metaslab_trace_max_entries = 5000;
+#endif
+
+static uint64_t metaslab_weight(metaslab_t *);
+static void metaslab_set_fragmentation(metaslab_t *);
+
+#ifdef _METASLAB_TRACING
+kmem_cache_t *metaslab_alloc_trace_cache;
+#endif
/*
* ==========================================================================
mc->mc_spa = spa;
mc->mc_rotor = NULL;
mc->mc_ops = ops;
- mutex_init(&mc->mc_fastwrite_lock, NULL, MUTEX_DEFAULT, NULL);
+ mutex_init(&mc->mc_lock, NULL, MUTEX_DEFAULT, NULL);
+ refcount_create_tracked(&mc->mc_alloc_slots);
return (mc);
}
ASSERT(mc->mc_space == 0);
ASSERT(mc->mc_dspace == 0);
- mutex_destroy(&mc->mc_fastwrite_lock);
+ refcount_destroy(&mc->mc_alloc_slots);
+ mutex_destroy(&mc->mc_lock);
kmem_free(mc, sizeof (metaslab_class_t));
}
continue;
}
- space += tvd->vdev_max_asize - tvd->vdev_asize;
+ /*
+ * Calculate if we have enough space to add additional
+ * metaslabs. We report the expandable space in terms
+ * of the metaslab size since that's the unit of expansion.
+ */
+ space += P2ALIGN(tvd->vdev_max_asize - tvd->vdev_asize,
+ 1ULL << tvd->vdev_ms_shift);
}
spa_config_exit(mc->mc_spa, SCL_VDEV, FTAG);
return (space);
}
-/*
- * ==========================================================================
- * Metaslab groups
- * ==========================================================================
- */
static int
metaslab_compare(const void *x1, const void *x2)
{
- const metaslab_t *m1 = x1;
- const metaslab_t *m2 = x2;
+ const metaslab_t *m1 = (const metaslab_t *)x1;
+ const metaslab_t *m2 = (const metaslab_t *)x2;
+
+ int cmp = AVL_CMP(m2->ms_weight, m1->ms_weight);
+ if (likely(cmp))
+ return (cmp);
+
+ IMPLY(AVL_CMP(m1->ms_start, m2->ms_start) == 0, m1 == m2);
+
+ return (AVL_CMP(m1->ms_start, m2->ms_start));
+}
+
+/*
+ * Verify that the space accounting on disk matches the in-core range_trees.
+ */
+void
+metaslab_verify_space(metaslab_t *msp, uint64_t txg)
+{
+ spa_t *spa = msp->ms_group->mg_vd->vdev_spa;
+ uint64_t allocated = 0;
+ uint64_t sm_free_space, msp_free_space;
+ int t;
+
+ ASSERT(MUTEX_HELD(&msp->ms_lock));
- if (m1->ms_weight < m2->ms_weight)
- return (1);
- if (m1->ms_weight > m2->ms_weight)
- return (-1);
+ if ((zfs_flags & ZFS_DEBUG_METASLAB_VERIFY) == 0)
+ return;
/*
- * If the weights are identical, use the offset to force uniqueness.
+ * We can only verify the metaslab space when we're called
+ * from syncing context with a loaded metaslab that has an allocated
+ * space map. Calling this in non-syncing context does not
+ * provide a consistent view of the metaslab since we're performing
+ * allocations in the future.
*/
- if (m1->ms_start < m2->ms_start)
- return (-1);
- if (m1->ms_start > m2->ms_start)
- return (1);
+ if (txg != spa_syncing_txg(spa) || msp->ms_sm == NULL ||
+ !msp->ms_loaded)
+ return;
- ASSERT3P(m1, ==, m2);
+ sm_free_space = msp->ms_size - space_map_allocated(msp->ms_sm) -
+ space_map_alloc_delta(msp->ms_sm);
- return (0);
+ /*
+ * Account for future allocations since we would have already
+ * deducted that space from the ms_freetree.
+ */
+ for (t = 0; t < TXG_CONCURRENT_STATES; t++) {
+ allocated +=
+ range_tree_space(msp->ms_alloctree[(txg + t) & TXG_MASK]);
+ }
+
+ msp_free_space = range_tree_space(msp->ms_tree) + allocated +
+ msp->ms_deferspace + range_tree_space(msp->ms_freedtree);
+
+ VERIFY3U(sm_free_space, ==, msp_free_space);
}
+/*
+ * ==========================================================================
+ * Metaslab groups
+ * ==========================================================================
+ */
/*
* Update the allocatable flag and the metaslab group's capacity.
* The allocatable flag is set to true if the capacity is below
- * the zfs_mg_noalloc_threshold. If a metaslab group transitions
- * from allocatable to non-allocatable or vice versa then the metaslab
- * group's class is updated to reflect the transition.
+ * the zfs_mg_noalloc_threshold or has a fragmentation value that is
+ * greater than zfs_mg_fragmentation_threshold. If a metaslab group
+ * transitions from allocatable to non-allocatable or vice versa then the
+ * metaslab group's class is updated to reflect the transition.
*/
static void
metaslab_group_alloc_update(metaslab_group_t *mg)
metaslab_class_t *mc = mg->mg_class;
vdev_stat_t *vs = &vd->vdev_stat;
boolean_t was_allocatable;
+ boolean_t was_initialized;
ASSERT(vd == vd->vdev_top);
mutex_enter(&mg->mg_lock);
was_allocatable = mg->mg_allocatable;
+ was_initialized = mg->mg_initialized;
mg->mg_free_capacity = ((vs->vs_space - vs->vs_alloc) * 100) /
(vs->vs_space + 1);
+ mutex_enter(&mc->mc_lock);
+
+ /*
+ * If the metaslab group was just added then it won't
+ * have any space until we finish syncing out this txg.
+ * At that point we will consider it initialized and available
+ * for allocations. We also don't consider non-activated
+ * metaslab groups (e.g. vdevs that are in the middle of being removed)
+ * to be initialized, because they can't be used for allocation.
+ */
+ mg->mg_initialized = metaslab_group_initialized(mg);
+ if (!was_initialized && mg->mg_initialized) {
+ mc->mc_groups++;
+ } else if (was_initialized && !mg->mg_initialized) {
+ ASSERT3U(mc->mc_groups, >, 0);
+ mc->mc_groups--;
+ }
+ if (mg->mg_initialized)
+ mg->mg_no_free_space = B_FALSE;
+
/*
* A metaslab group is considered allocatable if it has plenty
* of free space or is not heavily fragmented. We only take
* fragmentation into account if the metaslab group has a valid
* fragmentation metric (i.e. a value between 0 and 100).
*/
- mg->mg_allocatable = (mg->mg_free_capacity > zfs_mg_noalloc_threshold &&
+ mg->mg_allocatable = (mg->mg_activation_count > 0 &&
+ mg->mg_free_capacity > zfs_mg_noalloc_threshold &&
(mg->mg_fragmentation == ZFS_FRAG_INVALID ||
mg->mg_fragmentation <= zfs_mg_fragmentation_threshold));
mc->mc_alloc_groups--;
else if (!was_allocatable && mg->mg_allocatable)
mc->mc_alloc_groups++;
+ mutex_exit(&mc->mc_lock);
mutex_exit(&mg->mg_lock);
}
mg->mg_vd = vd;
mg->mg_class = mc;
mg->mg_activation_count = 0;
+ mg->mg_initialized = B_FALSE;
+ mg->mg_no_free_space = B_TRUE;
+ refcount_create_tracked(&mg->mg_alloc_queue_depth);
mg->mg_taskq = taskq_create("metaslab_group_taskq", metaslab_load_pct,
maxclsyspri, 10, INT_MAX, TASKQ_THREADS_CPU_PCT | TASKQ_DYNAMIC);
taskq_destroy(mg->mg_taskq);
avl_destroy(&mg->mg_metaslab_tree);
mutex_destroy(&mg->mg_lock);
+ refcount_destroy(&mg->mg_alloc_queue_depth);
kmem_free(mg, sizeof (metaslab_group_t));
}
mg->mg_next = NULL;
}
+boolean_t
+metaslab_group_initialized(metaslab_group_t *mg)
+{
+ vdev_t *vd = mg->mg_vd;
+ vdev_stat_t *vs = &vd->vdev_stat;
+
+ return (vs->vs_space != 0 && mg->mg_activation_count > 0);
+}
+
uint64_t
metaslab_group_get_space(metaslab_group_t *mg)
{
* group should avoid allocations if its free capacity is less than the
* zfs_mg_noalloc_threshold or its fragmentation metric is greater than
* zfs_mg_fragmentation_threshold and there is at least one metaslab group
- * that can still handle allocations.
+ * that can still handle allocations. If the allocation throttle is enabled
+ * then we skip allocations to devices that have reached their maximum
+ * allocation queue depth unless the selected metaslab group is the only
+ * eligible group remaining.
*/
static boolean_t
-metaslab_group_allocatable(metaslab_group_t *mg)
+metaslab_group_allocatable(metaslab_group_t *mg, metaslab_group_t *rotor,
+ uint64_t psize)
{
- vdev_t *vd = mg->mg_vd;
- spa_t *spa = vd->vdev_spa;
+ spa_t *spa = mg->mg_vd->vdev_spa;
metaslab_class_t *mc = mg->mg_class;
/*
- * We use two key metrics to determine if a metaslab group is
- * considered allocatable -- free space and fragmentation. If
- * the free space is greater than the free space threshold and
- * the fragmentation is less than the fragmentation threshold then
- * consider the group allocatable. There are two case when we will
- * not consider these key metrics. The first is if the group is
- * associated with a slog device and the second is if all groups
- * in this metaslab class have already been consider ineligible
+ * We can only consider skipping this metaslab group if it's
+ * in the normal metaslab class and there are other metaslab
+ * groups to select from. Otherwise, we always consider it eligible
* for allocations.
*/
- return ((mg->mg_free_capacity > zfs_mg_noalloc_threshold &&
- (mg->mg_fragmentation == ZFS_FRAG_INVALID ||
- mg->mg_fragmentation <= zfs_mg_fragmentation_threshold)) ||
- mc != spa_normal_class(spa) || mc->mc_alloc_groups == 0);
+ if (mc != spa_normal_class(spa) || mc->mc_groups <= 1)
+ return (B_TRUE);
+
+ /*
+ * If the metaslab group's mg_allocatable flag is set (see comments
+ * in metaslab_group_alloc_update() for more information) and
+ * the allocation throttle is disabled then allow allocations to this
+ * device. However, if the allocation throttle is enabled then
+ * check if we have reached our allocation limit (mg_alloc_queue_depth)
+ * to determine if we should allow allocations to this metaslab group.
+ * If all metaslab groups are no longer considered allocatable
+ * (mc_alloc_groups == 0) or we're trying to allocate the smallest
+ * gang block size then we allow allocations on this metaslab group
+ * regardless of the mg_allocatable or throttle settings.
+ */
+ if (mg->mg_allocatable) {
+ metaslab_group_t *mgp;
+ int64_t qdepth;
+ uint64_t qmax = mg->mg_max_alloc_queue_depth;
+
+ if (!mc->mc_alloc_throttle_enabled)
+ return (B_TRUE);
+
+ /*
+ * If this metaslab group does not have any free space, then
+ * there is no point in looking further.
+ */
+ if (mg->mg_no_free_space)
+ return (B_FALSE);
+
+ qdepth = refcount_count(&mg->mg_alloc_queue_depth);
+
+ /*
+ * If this metaslab group is below its qmax or it's
+ * the only allocatable metasable group, then attempt
+ * to allocate from it.
+ */
+ if (qdepth < qmax || mc->mc_alloc_groups == 1)
+ return (B_TRUE);
+ ASSERT3U(mc->mc_alloc_groups, >, 1);
+
+ /*
+ * Since this metaslab group is at or over its qmax, we
+ * need to determine if there are metaslab groups after this
+ * one that might be able to handle this allocation. This is
+ * racy since we can't hold the locks for all metaslab
+ * groups at the same time when we make this check.
+ */
+ for (mgp = mg->mg_next; mgp != rotor; mgp = mgp->mg_next) {
+ qmax = mgp->mg_max_alloc_queue_depth;
+
+ qdepth = refcount_count(&mgp->mg_alloc_queue_depth);
+
+ /*
+ * If there is another metaslab group that
+ * might be able to handle the allocation, then
+ * we return false so that we skip this group.
+ */
+ if (qdepth < qmax && !mgp->mg_no_free_space)
+ return (B_FALSE);
+ }
+
+ /*
+ * We didn't find another group to handle the allocation
+ * so we can't skip this metaslab group even though
+ * we are at or over our qmax.
+ */
+ return (B_TRUE);
+
+ } else if (mc->mc_alloc_groups == 0 || psize == SPA_MINBLOCKSIZE) {
+ return (B_TRUE);
+ }
+ return (B_FALSE);
}
/*
uint64_t rs_size1 = r1->rs_end - r1->rs_start;
uint64_t rs_size2 = r2->rs_end - r2->rs_start;
- if (rs_size1 < rs_size2)
- return (-1);
- if (rs_size1 > rs_size2)
- return (1);
+ int cmp = AVL_CMP(rs_size1, rs_size2);
+ if (likely(cmp))
+ return (cmp);
- if (r1->rs_start < r2->rs_start)
- return (-1);
-
- if (r1->rs_start > r2->rs_start)
- return (1);
-
- return (0);
+ return (AVL_CMP(r1->rs_start, r2->rs_start));
}
/*
/*
* ==========================================================================
- * Metaslab block operations
+ * Common allocator routines
* ==========================================================================
*/
return (rs->rs_end - rs->rs_start);
}
-uint64_t
-metaslab_block_alloc(metaslab_t *msp, uint64_t size)
+static range_seg_t *
+metaslab_block_find(avl_tree_t *t, uint64_t start, uint64_t size)
{
- uint64_t start;
- range_tree_t *rt = msp->ms_tree;
-
- VERIFY(!msp->ms_condensing);
+ range_seg_t *rs, rsearch;
+ avl_index_t where;
- start = msp->ms_ops->msop_alloc(msp, size);
- if (start != -1ULL) {
- vdev_t *vd = msp->ms_group->mg_vd;
+ rsearch.rs_start = start;
+ rsearch.rs_end = start + size;
- VERIFY0(P2PHASE(start, 1ULL << vd->vdev_ashift));
- VERIFY0(P2PHASE(size, 1ULL << vd->vdev_ashift));
- VERIFY3U(range_tree_space(rt) - size, <=, msp->ms_size);
- range_tree_remove(rt, start, size);
+ rs = avl_find(t, &rsearch, &where);
+ if (rs == NULL) {
+ rs = avl_nearest(t, where, AVL_AFTER);
}
- return (start);
-}
-/*
- * ==========================================================================
- * Common allocator routines
- * ==========================================================================
- */
+ return (rs);
+}
#if defined(WITH_FF_BLOCK_ALLOCATOR) || \
defined(WITH_DF_BLOCK_ALLOCATOR) || \
metaslab_block_picker(avl_tree_t *t, uint64_t *cursor, uint64_t size,
uint64_t align)
{
- range_seg_t *rs, rsearch;
- avl_index_t where;
-
- rsearch.rs_start = *cursor;
- rsearch.rs_end = *cursor + size;
-
- rs = avl_find(t, &rsearch, &where);
- if (rs == NULL)
- rs = avl_nearest(t, where, AVL_AFTER);
+ range_seg_t *rs = metaslab_block_find(t, *cursor, size);
while (rs != NULL) {
uint64_t offset = P2ROUNDUP(rs->rs_start, align);
{
int error = 0;
int t;
+ boolean_t success = B_FALSE;
ASSERT(MUTEX_HELD(&msp->ms_lock));
ASSERT(!msp->ms_loaded);
else
range_tree_add(msp->ms_tree, msp->ms_start, msp->ms_size);
- msp->ms_loaded = (error == 0);
+ success = (error == 0);
msp->ms_loading = B_FALSE;
- if (msp->ms_loaded) {
+ if (success) {
+ ASSERT3P(msp->ms_group, !=, NULL);
+ msp->ms_loaded = B_TRUE;
+
for (t = 0; t < TXG_DEFER_SIZE; t++) {
range_tree_walk(msp->ms_defertree[t],
range_tree_remove, msp->ms_tree);
}
+ msp->ms_max_size = metaslab_block_maxsize(msp);
}
cv_broadcast(&msp->ms_load_cv);
return (error);
range_tree_vacate(msp->ms_tree, NULL, NULL);
msp->ms_loaded = B_FALSE;
msp->ms_weight &= ~METASLAB_ACTIVE_MASK;
+ msp->ms_max_size = 0;
}
int
/*
* We create the main range tree here, but we don't create the
- * alloctree and freetree until metaslab_sync_done(). This serves
+ * other range trees until metaslab_sync_done(). This serves
* two purposes: it allows metaslab_sync_done() to detect the
* addition of new space; and for debugging, it ensures that we'd
* data fault on any attempt to use this metaslab before it's ready.
ms->ms_tree = range_tree_create(&metaslab_rt_ops, ms, &ms->ms_lock);
metaslab_group_add(mg, ms);
- ms->ms_fragmentation = metaslab_fragmentation(ms);
- ms->ms_ops = mg->mg_class->mc_ops;
+ metaslab_set_fragmentation(ms);
/*
* If we're opening an existing pool (txg == 0) or creating
* a new one (txg == TXG_INITIAL), all space is available now.
* If we're adding space to an existing pool, the new space
* does not become available until after this txg has synced.
+ * The metaslab's weight will also be initialized when we sync
+ * out this txg. This ensures that we don't attempt to allocate
+ * from it before we have initialized it completely.
*/
if (txg <= TXG_INITIAL)
metaslab_sync_done(ms, 0);
/*
* If metaslab_debug_load is set and we're initializing a metaslab
- * that has an allocated space_map object then load the its space
+ * that has an allocated space map object then load the its space
* map so that can verify frees.
*/
if (metaslab_debug_load && ms->ms_sm != NULL) {
metaslab_group_remove(mg, msp);
mutex_enter(&msp->ms_lock);
-
VERIFY(msp->ms_group == NULL);
vdev_space_update(mg->mg_vd, -space_map_allocated(msp->ms_sm),
0, -msp->ms_size);
metaslab_unload(msp);
range_tree_destroy(msp->ms_tree);
+ range_tree_destroy(msp->ms_freeingtree);
+ range_tree_destroy(msp->ms_freedtree);
for (t = 0; t < TXG_SIZE; t++) {
range_tree_destroy(msp->ms_alloctree[t]);
- range_tree_destroy(msp->ms_freetree[t]);
}
for (t = 0; t < TXG_DEFER_SIZE; t++) {
* not support this metric. Otherwise, the return value should be in the
* range [0, 100].
*/
-static uint64_t
-metaslab_fragmentation(metaslab_t *msp)
+static void
+metaslab_set_fragmentation(metaslab_t *msp)
{
spa_t *spa = msp->ms_group->mg_vd->vdev_spa;
uint64_t fragmentation = 0;
SPA_FEATURE_SPACEMAP_HISTOGRAM);
int i;
- if (!feature_enabled)
- return (ZFS_FRAG_INVALID);
+ if (!feature_enabled) {
+ msp->ms_fragmentation = ZFS_FRAG_INVALID;
+ return;
+ }
/*
* A null space map means that the entire metaslab is free
* and thus is not fragmented.
*/
- if (msp->ms_sm == NULL)
- return (0);
+ if (msp->ms_sm == NULL) {
+ msp->ms_fragmentation = 0;
+ return;
+ }
/*
- * If this metaslab's space_map has not been upgraded, flag it
+ * If this metaslab's space map has not been upgraded, flag it
* so that we upgrade next time we encounter it.
*/
if (msp->ms_sm->sm_dbuf->db_size != sizeof (space_map_phys_t)) {
+ uint64_t txg = spa_syncing_txg(spa);
vdev_t *vd = msp->ms_group->mg_vd;
- if (spa_writeable(vd->vdev_spa)) {
- uint64_t txg = spa_syncing_txg(spa);
-
+ /*
+ * If we've reached the final dirty txg, then we must
+ * be shutting down the pool. We don't want to dirty
+ * any data past this point so skip setting the condense
+ * flag. We can retry this action the next time the pool
+ * is imported.
+ */
+ if (spa_writeable(spa) && txg < spa_final_dirty_txg(spa)) {
msp->ms_condense_wanted = B_TRUE;
vdev_dirty(vd, VDD_METASLAB, msp, txg + 1);
spa_dbgmsg(spa, "txg %llu, requesting force condense: "
- "msp %p, vd %p", txg, msp, vd);
+ "ms_id %llu, vdev_id %llu", txg, msp->ms_id,
+ vd->vdev_id);
}
- return (ZFS_FRAG_INVALID);
+ msp->ms_fragmentation = ZFS_FRAG_INVALID;
+ return;
}
for (i = 0; i < SPACE_MAP_HISTOGRAM_SIZE; i++) {
uint64_t space = 0;
uint8_t shift = msp->ms_sm->sm_shift;
+
int idx = MIN(shift - SPA_MINBLOCKSHIFT + i,
FRAGMENTATION_TABLE_SIZE - 1);
if (total > 0)
fragmentation /= total;
ASSERT3U(fragmentation, <=, 100);
- return (fragmentation);
+
+ msp->ms_fragmentation = fragmentation;
}
/*
* the LBA range, and whether the metaslab is loaded.
*/
static uint64_t
-metaslab_weight(metaslab_t *msp)
+metaslab_space_weight(metaslab_t *msp)
{
metaslab_group_t *mg = msp->ms_group;
vdev_t *vd = mg->mg_vd;
uint64_t weight, space;
ASSERT(MUTEX_HELD(&msp->ms_lock));
-
- /*
- * This vdev is in the process of being removed so there is nothing
- * for us to do here.
- */
- if (vd->vdev_removing) {
- ASSERT0(space_map_allocated(msp->ms_sm));
- ASSERT0(vd->vdev_ms_shift);
- return (0);
- }
+ ASSERT(!vd->vdev_removing);
/*
* The baseline weight is the metaslab's free space.
*/
space = msp->ms_size - space_map_allocated(msp->ms_sm);
- msp->ms_fragmentation = metaslab_fragmentation(msp);
if (metaslab_fragmentation_factor_enabled &&
msp->ms_fragmentation != ZFS_FRAG_INVALID) {
/*
weight |= (msp->ms_weight & METASLAB_ACTIVE_MASK);
}
+ WEIGHT_SET_SPACEBASED(weight);
return (weight);
}
-static int
-metaslab_activate(metaslab_t *msp, uint64_t activation_weight)
+/*
+ * Return the weight of the specified metaslab, according to the segment-based
+ * weighting algorithm. The metaslab must be loaded. This function can
+ * be called within a sync pass since it relies only on the metaslab's
+ * range tree which is always accurate when the metaslab is loaded.
+ */
+static uint64_t
+metaslab_weight_from_range_tree(metaslab_t *msp)
{
- ASSERT(MUTEX_HELD(&msp->ms_lock));
-
- if ((msp->ms_weight & METASLAB_ACTIVE_MASK) == 0) {
- metaslab_load_wait(msp);
- if (!msp->ms_loaded) {
- int error = metaslab_load(msp);
- if (error) {
- metaslab_group_sort(msp->ms_group, msp, 0);
- return (error);
- }
- }
+ uint64_t weight = 0;
+ uint32_t segments = 0;
+ int i;
- metaslab_group_sort(msp->ms_group, msp,
- msp->ms_weight | activation_weight);
- }
ASSERT(msp->ms_loaded);
- ASSERT(msp->ms_weight & METASLAB_ACTIVE_MASK);
- return (0);
+ for (i = RANGE_TREE_HISTOGRAM_SIZE - 1; i >= SPA_MINBLOCKSHIFT; i--) {
+ uint8_t shift = msp->ms_group->mg_vd->vdev_ashift;
+ int max_idx = SPACE_MAP_HISTOGRAM_SIZE + shift - 1;
+
+ segments <<= 1;
+ segments += msp->ms_tree->rt_histogram[i];
+
+ /*
+ * The range tree provides more precision than the space map
+ * and must be downgraded so that all values fit within the
+ * space map's histogram. This allows us to compare loaded
+ * vs. unloaded metaslabs to determine which metaslab is
+ * considered "best".
+ */
+ if (i > max_idx)
+ continue;
+
+ if (segments != 0) {
+ WEIGHT_SET_COUNT(weight, segments);
+ WEIGHT_SET_INDEX(weight, i);
+ WEIGHT_SET_ACTIVE(weight, 0);
+ break;
+ }
+ }
+ return (weight);
}
-static void
-metaslab_passivate(metaslab_t *msp, uint64_t size)
+/*
+ * Calculate the weight based on the on-disk histogram. This should only
+ * be called after a sync pass has completely finished since the on-disk
+ * information is updated in metaslab_sync().
+ */
+static uint64_t
+metaslab_weight_from_spacemap(metaslab_t *msp)
{
- /*
- * If size < SPA_MINBLOCKSIZE, then we will not allocate from
- * this metaslab again. In that case, it had better be empty,
- * or we would be leaving space on the table.
- */
- ASSERT(size >= SPA_MINBLOCKSIZE || range_tree_space(msp->ms_tree) == 0);
- metaslab_group_sort(msp->ms_group, msp, MIN(msp->ms_weight, size));
- ASSERT((msp->ms_weight & METASLAB_ACTIVE_MASK) == 0);
+ uint64_t weight = 0;
+ int i;
+
+ for (i = SPACE_MAP_HISTOGRAM_SIZE - 1; i >= 0; i--) {
+ if (msp->ms_sm->sm_phys->smp_histogram[i] != 0) {
+ WEIGHT_SET_COUNT(weight,
+ msp->ms_sm->sm_phys->smp_histogram[i]);
+ WEIGHT_SET_INDEX(weight, i +
+ msp->ms_sm->sm_shift);
+ WEIGHT_SET_ACTIVE(weight, 0);
+ break;
+ }
+ }
+ return (weight);
}
-static void
-metaslab_preload(void *arg)
+/*
+ * Compute a segment-based weight for the specified metaslab. The weight
+ * is determined by highest bucket in the histogram. The information
+ * for the highest bucket is encoded into the weight value.
+ */
+static uint64_t
+metaslab_segment_weight(metaslab_t *msp)
{
- metaslab_t *msp = arg;
- spa_t *spa = msp->ms_group->mg_vd->vdev_spa;
- fstrans_cookie_t cookie = spl_fstrans_mark();
-
- ASSERT(!MUTEX_HELD(&msp->ms_group->mg_lock));
+ metaslab_group_t *mg = msp->ms_group;
+ uint64_t weight = 0;
+ uint8_t shift = mg->mg_vd->vdev_ashift;
- mutex_enter(&msp->ms_lock);
- metaslab_load_wait(msp);
- if (!msp->ms_loaded)
- (void) metaslab_load(msp);
+ ASSERT(MUTEX_HELD(&msp->ms_lock));
/*
- * Set the ms_access_txg value so that we don't unload it right away.
+ * The metaslab is completely free.
*/
- msp->ms_access_txg = spa_syncing_txg(spa) + metaslab_unload_delay + 1;
- mutex_exit(&msp->ms_lock);
- spl_fstrans_unmark(cookie);
-}
+ if (space_map_allocated(msp->ms_sm) == 0) {
+ int idx = highbit64(msp->ms_size) - 1;
+ int max_idx = SPACE_MAP_HISTOGRAM_SIZE + shift - 1;
-static void
-metaslab_group_preload(metaslab_group_t *mg)
-{
- spa_t *spa = mg->mg_vd->vdev_spa;
- metaslab_t *msp;
- avl_tree_t *t = &mg->mg_metaslab_tree;
- int m = 0;
+ if (idx < max_idx) {
+ WEIGHT_SET_COUNT(weight, 1ULL);
+ WEIGHT_SET_INDEX(weight, idx);
+ } else {
+ WEIGHT_SET_COUNT(weight, 1ULL << (idx - max_idx));
+ WEIGHT_SET_INDEX(weight, max_idx);
+ }
+ WEIGHT_SET_ACTIVE(weight, 0);
+ ASSERT(!WEIGHT_IS_SPACEBASED(weight));
- if (spa_shutting_down(spa) || !metaslab_preload_enabled) {
- taskq_wait_outstanding(mg->mg_taskq, 0);
- return;
+ return (weight);
}
- mutex_enter(&mg->mg_lock);
+ ASSERT3U(msp->ms_sm->sm_dbuf->db_size, ==, sizeof (space_map_phys_t));
+
/*
- * Load the next potential metaslabs
+ * If the metaslab is fully allocated then just make the weight 0.
+ */
+ if (space_map_allocated(msp->ms_sm) == msp->ms_size)
+ return (0);
+ /*
+ * If the metaslab is already loaded, then use the range tree to
+ * determine the weight. Otherwise, we rely on the space map information
+ * to generate the weight.
*/
- msp = avl_first(t);
- while (msp != NULL) {
- metaslab_t *msp_next = AVL_NEXT(t, msp);
+ if (msp->ms_loaded) {
+ weight = metaslab_weight_from_range_tree(msp);
+ } else {
+ weight = metaslab_weight_from_spacemap(msp);
+ }
- /*
- * We preload only the maximum number of metaslabs specified
- * by metaslab_preload_limit. If a metaslab is being forced
- * to condense then we preload it too. This will ensure
- * that force condensing happens in the next txg.
- */
- if (++m > metaslab_preload_limit && !msp->ms_condense_wanted) {
- msp = msp_next;
- continue;
+ /*
+ * If the metaslab was active the last time we calculated its weight
+ * then keep it active. We want to consume the entire region that
+ * is associated with this weight.
+ */
+ if (msp->ms_activation_weight != 0 && weight != 0)
+ WEIGHT_SET_ACTIVE(weight, WEIGHT_GET_ACTIVE(msp->ms_weight));
+ return (weight);
+}
+
+/*
+ * Determine if we should attempt to allocate from this metaslab. If the
+ * metaslab has a maximum size then we can quickly determine if the desired
+ * allocation size can be satisfied. Otherwise, if we're using segment-based
+ * weighting then we can determine the maximum allocation that this metaslab
+ * can accommodate based on the index encoded in the weight. If we're using
+ * space-based weights then rely on the entire weight (excluding the weight
+ * type bit).
+ */
+boolean_t
+metaslab_should_allocate(metaslab_t *msp, uint64_t asize)
+{
+ boolean_t should_allocate;
+
+ if (msp->ms_max_size != 0)
+ return (msp->ms_max_size >= asize);
+
+ if (!WEIGHT_IS_SPACEBASED(msp->ms_weight)) {
+ /*
+ * The metaslab segment weight indicates segments in the
+ * range [2^i, 2^(i+1)), where i is the index in the weight.
+ * Since the asize might be in the middle of the range, we
+ * should attempt the allocation if asize < 2^(i+1).
+ */
+ should_allocate = (asize <
+ 1ULL << (WEIGHT_GET_INDEX(msp->ms_weight) + 1));
+ } else {
+ should_allocate = (asize <=
+ (msp->ms_weight & ~METASLAB_WEIGHT_TYPE));
+ }
+ return (should_allocate);
+}
+static uint64_t
+metaslab_weight(metaslab_t *msp)
+{
+ vdev_t *vd = msp->ms_group->mg_vd;
+ spa_t *spa = vd->vdev_spa;
+ uint64_t weight;
+
+ ASSERT(MUTEX_HELD(&msp->ms_lock));
+
+ /*
+ * This vdev is in the process of being removed so there is nothing
+ * for us to do here.
+ */
+ if (vd->vdev_removing) {
+ ASSERT0(space_map_allocated(msp->ms_sm));
+ ASSERT0(vd->vdev_ms_shift);
+ return (0);
+ }
+
+ metaslab_set_fragmentation(msp);
+
+ /*
+ * Update the maximum size if the metaslab is loaded. This will
+ * ensure that we get an accurate maximum size if newly freed space
+ * has been added back into the free tree.
+ */
+ if (msp->ms_loaded)
+ msp->ms_max_size = metaslab_block_maxsize(msp);
+
+ /*
+ * Segment-based weighting requires space map histogram support.
+ */
+ if (zfs_metaslab_segment_weight_enabled &&
+ spa_feature_is_enabled(spa, SPA_FEATURE_SPACEMAP_HISTOGRAM) &&
+ (msp->ms_sm == NULL || msp->ms_sm->sm_dbuf->db_size ==
+ sizeof (space_map_phys_t))) {
+ weight = metaslab_segment_weight(msp);
+ } else {
+ weight = metaslab_space_weight(msp);
+ }
+ return (weight);
+}
+
+static int
+metaslab_activate(metaslab_t *msp, uint64_t activation_weight)
+{
+ ASSERT(MUTEX_HELD(&msp->ms_lock));
+
+ if ((msp->ms_weight & METASLAB_ACTIVE_MASK) == 0) {
+ metaslab_load_wait(msp);
+ if (!msp->ms_loaded) {
+ int error = metaslab_load(msp);
+ if (error) {
+ metaslab_group_sort(msp->ms_group, msp, 0);
+ return (error);
+ }
}
+ msp->ms_activation_weight = msp->ms_weight;
+ metaslab_group_sort(msp->ms_group, msp,
+ msp->ms_weight | activation_weight);
+ }
+ ASSERT(msp->ms_loaded);
+ ASSERT(msp->ms_weight & METASLAB_ACTIVE_MASK);
+
+ return (0);
+}
+
+static void
+metaslab_passivate(metaslab_t *msp, uint64_t weight)
+{
+ ASSERTV(uint64_t size = weight & ~METASLAB_WEIGHT_TYPE);
+
+ /*
+ * If size < SPA_MINBLOCKSIZE, then we will not allocate from
+ * this metaslab again. In that case, it had better be empty,
+ * or we would be leaving space on the table.
+ */
+ ASSERT(size >= SPA_MINBLOCKSIZE ||
+ range_tree_space(msp->ms_tree) == 0);
+ ASSERT0(weight & METASLAB_ACTIVE_MASK);
+
+ msp->ms_activation_weight = 0;
+ metaslab_group_sort(msp->ms_group, msp, weight);
+ ASSERT((msp->ms_weight & METASLAB_ACTIVE_MASK) == 0);
+}
+
+/*
+ * Segment-based metaslabs are activated once and remain active until
+ * we either fail an allocation attempt (similar to space-based metaslabs)
+ * or have exhausted the free space in zfs_metaslab_switch_threshold
+ * buckets since the metaslab was activated. This function checks to see
+ * if we've exhaused the zfs_metaslab_switch_threshold buckets in the
+ * metaslab and passivates it proactively. This will allow us to select a
+ * metaslab with a larger contiguous region, if any, remaining within this
+ * metaslab group. If we're in sync pass > 1, then we continue using this
+ * metaslab so that we don't dirty more block and cause more sync passes.
+ */
+void
+metaslab_segment_may_passivate(metaslab_t *msp)
+{
+ spa_t *spa = msp->ms_group->mg_vd->vdev_spa;
+ uint64_t weight;
+ int activation_idx, current_idx;
+
+ if (WEIGHT_IS_SPACEBASED(msp->ms_weight) || spa_sync_pass(spa) > 1)
+ return;
+
+ /*
+ * Since we are in the middle of a sync pass, the most accurate
+ * information that is accessible to us is the in-core range tree
+ * histogram; calculate the new weight based on that information.
+ */
+ weight = metaslab_weight_from_range_tree(msp);
+ activation_idx = WEIGHT_GET_INDEX(msp->ms_activation_weight);
+ current_idx = WEIGHT_GET_INDEX(weight);
+
+ if (current_idx <= activation_idx - zfs_metaslab_switch_threshold)
+ metaslab_passivate(msp, weight);
+}
+
+static void
+metaslab_preload(void *arg)
+{
+ metaslab_t *msp = arg;
+ spa_t *spa = msp->ms_group->mg_vd->vdev_spa;
+ fstrans_cookie_t cookie = spl_fstrans_mark();
+
+ ASSERT(!MUTEX_HELD(&msp->ms_group->mg_lock));
+
+ mutex_enter(&msp->ms_lock);
+ metaslab_load_wait(msp);
+ if (!msp->ms_loaded)
+ (void) metaslab_load(msp);
+ msp->ms_selected_txg = spa_syncing_txg(spa);
+ mutex_exit(&msp->ms_lock);
+ spl_fstrans_unmark(cookie);
+}
+
+static void
+metaslab_group_preload(metaslab_group_t *mg)
+{
+ spa_t *spa = mg->mg_vd->vdev_spa;
+ metaslab_t *msp;
+ avl_tree_t *t = &mg->mg_metaslab_tree;
+ int m = 0;
+
+ if (spa_shutting_down(spa) || !metaslab_preload_enabled) {
+ taskq_wait_outstanding(mg->mg_taskq, 0);
+ return;
+ }
+
+ mutex_enter(&mg->mg_lock);
+ /*
+ * Load the next potential metaslabs
+ */
+ for (msp = avl_first(t); msp != NULL; msp = AVL_NEXT(t, msp)) {
/*
- * We must drop the metaslab group lock here to preserve
- * lock ordering with the ms_lock (when grabbing both
- * the mg_lock and the ms_lock, the ms_lock must be taken
- * first). As a result, it is possible that the ordering
- * of the metaslabs within the avl tree may change before
- * we reacquire the lock. The metaslab cannot be removed from
- * the tree while we're in syncing context so it is safe to
- * drop the mg_lock here. If the metaslabs are reordered
- * nothing will break -- we just may end up loading a
- * less than optimal one.
+ * We preload only the maximum number of metaslabs specified
+ * by metaslab_preload_limit. If a metaslab is being forced
+ * to condense then we preload it too. This will ensure
+ * that force condensing happens in the next txg.
*/
- mutex_exit(&mg->mg_lock);
+ if (++m > metaslab_preload_limit && !msp->ms_condense_wanted) {
+ continue;
+ }
+
VERIFY(taskq_dispatch(mg->mg_taskq, metaslab_preload,
- msp, TQ_SLEEP) != 0);
- mutex_enter(&mg->mg_lock);
- msp = msp_next;
+ msp, TQ_SLEEP) != TASKQID_INVALID);
}
mutex_exit(&mg->mg_lock);
}
range_seg_t *rs;
uint64_t size, entries, segsz, object_size, optimal_size, record_size;
dmu_object_info_t doi;
- uint64_t vdev_blocksize = 1 << msp->ms_group->mg_vd->vdev_ashift;
+ uint64_t vdev_blocksize = 1ULL << msp->ms_group->mg_vd->vdev_ashift;
ASSERT(MUTEX_HELD(&msp->ms_lock));
ASSERT(msp->ms_loaded);
metaslab_condense(metaslab_t *msp, uint64_t txg, dmu_tx_t *tx)
{
spa_t *spa = msp->ms_group->mg_vd->vdev_spa;
- range_tree_t *freetree = msp->ms_freetree[txg & TXG_MASK];
range_tree_t *condense_tree;
space_map_t *sm = msp->ms_sm;
int t;
ASSERT(msp->ms_loaded);
- spa_dbgmsg(spa, "condensing: txg %llu, msp[%llu] %p, "
- "smp size %llu, segments %lu, forcing condense=%s", txg,
- msp->ms_id, msp, space_map_length(msp->ms_sm),
- avl_numnodes(&msp->ms_tree->rt_root),
+ spa_dbgmsg(spa, "condensing: txg %llu, msp[%llu] %p, vdev id %llu, "
+ "spa %s, smp size %llu, segments %lu, forcing condense=%s", txg,
+ msp->ms_id, msp, msp->ms_group->mg_vd->vdev_id,
+ msp->ms_group->mg_vd->vdev_spa->spa_name,
+ space_map_length(msp->ms_sm), avl_numnodes(&msp->ms_tree->rt_root),
msp->ms_condense_wanted ? "TRUE" : "FALSE");
msp->ms_condense_wanted = B_FALSE;
/*
* Remove what's been freed in this txg from the condense_tree.
* Since we're in sync_pass 1, we know that all the frees from
- * this txg are in the freetree.
+ * this txg are in the freeingtree.
*/
- range_tree_walk(freetree, range_tree_remove, condense_tree);
+ range_tree_walk(msp->ms_freeingtree, range_tree_remove, condense_tree);
for (t = 0; t < TXG_DEFER_SIZE; t++) {
range_tree_walk(msp->ms_defertree[t],
mutex_enter(&msp->ms_lock);
/*
- * While we would ideally like to create a space_map representation
+ * While we would ideally like to create a space map representation
* that consists only of allocation records, doing so can be
* prohibitively expensive because the in-core free tree can be
* large, and therefore computationally expensive to subtract
spa_t *spa = vd->vdev_spa;
objset_t *mos = spa_meta_objset(spa);
range_tree_t *alloctree = msp->ms_alloctree[txg & TXG_MASK];
- range_tree_t **freetree = &msp->ms_freetree[txg & TXG_MASK];
- range_tree_t **freed_tree =
- &msp->ms_freetree[TXG_CLEAN(txg) & TXG_MASK];
dmu_tx_t *tx;
uint64_t object = space_map_object(msp->ms_sm);
/*
* This metaslab has just been added so there's no work to do now.
*/
- if (*freetree == NULL) {
+ if (msp->ms_freeingtree == NULL) {
ASSERT3P(alloctree, ==, NULL);
return;
}
ASSERT3P(alloctree, !=, NULL);
- ASSERT3P(*freetree, !=, NULL);
- ASSERT3P(*freed_tree, !=, NULL);
+ ASSERT3P(msp->ms_freeingtree, !=, NULL);
+ ASSERT3P(msp->ms_freedtree, !=, NULL);
/*
* Normally, we don't want to process a metaslab if there
* are no allocations or frees to perform. However, if the metaslab
- * is being forced to condense we need to let it through.
+ * is being forced to condense and it's loaded, we need to let it
+ * through.
*/
if (range_tree_space(alloctree) == 0 &&
- range_tree_space(*freetree) == 0 &&
- !msp->ms_condense_wanted)
+ range_tree_space(msp->ms_freeingtree) == 0 &&
+ !(msp->ms_loaded && msp->ms_condense_wanted))
return;
+
+ VERIFY(txg <= spa_final_dirty_txg(spa));
+
/*
* The only state that can actually be changing concurrently with
* metaslab_sync() is the metaslab's ms_tree. No other thread can
- * be modifying this txg's alloctree, freetree, freed_tree, or
+ * be modifying this txg's alloctree, freeingtree, freedtree, or
* space_map_phys_t. Therefore, we only hold ms_lock to satify
- * space_map ASSERTs. We drop it whenever we call into the DMU,
+ * space map ASSERTs. We drop it whenever we call into the DMU,
* because the DMU can call down to us (e.g. via zio_free()) at
* any time.
*/
mutex_enter(&msp->ms_lock);
/*
- * Note: metaslab_condense() clears the space_map's histogram.
- * Therefore we muse verify and remove this histogram before
+ * Note: metaslab_condense() clears the space map's histogram.
+ * Therefore we must verify and remove this histogram before
* condensing.
*/
metaslab_group_histogram_verify(mg);
metaslab_condense(msp, txg, tx);
} else {
space_map_write(msp->ms_sm, alloctree, SM_ALLOC, tx);
- space_map_write(msp->ms_sm, *freetree, SM_FREE, tx);
+ space_map_write(msp->ms_sm, msp->ms_freeingtree, SM_FREE, tx);
}
if (msp->ms_loaded) {
+ int t;
+
/*
* When the space map is loaded, we have an accruate
* histogram in the range tree. This gives us an opportunity
*/
space_map_histogram_clear(msp->ms_sm);
space_map_histogram_add(msp->ms_sm, msp->ms_tree, tx);
- } else {
+
/*
- * Since the space map is not loaded we simply update the
- * exisiting histogram with what was freed in this txg. This
- * means that the on-disk histogram may not have an accurate
- * view of the free space but it's close enough to allow
- * us to make allocation decisions.
+ * Since we've cleared the histogram we need to add back
+ * any free space that has already been processed, plus
+ * any deferred space. This allows the on-disk histogram
+ * to accurately reflect all free space even if some space
+ * is not yet available for allocation (i.e. deferred).
*/
- space_map_histogram_add(msp->ms_sm, *freetree, tx);
+ space_map_histogram_add(msp->ms_sm, msp->ms_freedtree, tx);
+
+ /*
+ * Add back any deferred free space that has not been
+ * added back into the in-core free tree yet. This will
+ * ensure that we don't end up with a space map histogram
+ * that is completely empty unless the metaslab is fully
+ * allocated.
+ */
+ for (t = 0; t < TXG_DEFER_SIZE; t++) {
+ space_map_histogram_add(msp->ms_sm,
+ msp->ms_defertree[t], tx);
+ }
}
+
+ /*
+ * Always add the free space from this sync pass to the space
+ * map histogram. We want to make sure that the on-disk histogram
+ * accounts for all free space. If the space map is not loaded,
+ * then we will lose some accuracy but will correct it the next
+ * time we load the space map.
+ */
+ space_map_histogram_add(msp->ms_sm, msp->ms_freeingtree, tx);
+
metaslab_group_histogram_add(mg, msp);
metaslab_group_histogram_verify(mg);
metaslab_class_histogram_verify(mg->mg_class);
/*
* For sync pass 1, we avoid traversing this txg's free range tree
- * and instead will just swap the pointers for freetree and
- * freed_tree. We can safely do this since the freed_tree is
+ * and instead will just swap the pointers for freeingtree and
+ * freedtree. We can safely do this since the freed_tree is
* guaranteed to be empty on the initial pass.
*/
if (spa_sync_pass(spa) == 1) {
- range_tree_swap(freetree, freed_tree);
+ range_tree_swap(&msp->ms_freeingtree, &msp->ms_freedtree);
} else {
- range_tree_vacate(*freetree, range_tree_add, *freed_tree);
+ range_tree_vacate(msp->ms_freeingtree,
+ range_tree_add, msp->ms_freedtree);
}
range_tree_vacate(alloctree, NULL, NULL);
ASSERT0(range_tree_space(msp->ms_alloctree[txg & TXG_MASK]));
- ASSERT0(range_tree_space(msp->ms_freetree[txg & TXG_MASK]));
+ ASSERT0(range_tree_space(msp->ms_alloctree[TXG_CLEAN(txg) & TXG_MASK]));
+ ASSERT0(range_tree_space(msp->ms_freeingtree));
mutex_exit(&msp->ms_lock);
{
metaslab_group_t *mg = msp->ms_group;
vdev_t *vd = mg->mg_vd;
- range_tree_t **freed_tree;
+ spa_t *spa = vd->vdev_spa;
range_tree_t **defer_tree;
int64_t alloc_delta, defer_delta;
+ uint64_t free_space;
+ boolean_t defer_allowed = B_TRUE;
int t;
ASSERT(!vd->vdev_ishole);
/*
* If this metaslab is just becoming available, initialize its
- * alloctrees, freetrees, and defertree and add its capacity to
- * the vdev.
+ * range trees and add its capacity to the vdev.
*/
- if (msp->ms_freetree[TXG_CLEAN(txg) & TXG_MASK] == NULL) {
+ if (msp->ms_freedtree == NULL) {
for (t = 0; t < TXG_SIZE; t++) {
ASSERT(msp->ms_alloctree[t] == NULL);
- ASSERT(msp->ms_freetree[t] == NULL);
msp->ms_alloctree[t] = range_tree_create(NULL, msp,
&msp->ms_lock);
- msp->ms_freetree[t] = range_tree_create(NULL, msp,
- &msp->ms_lock);
}
+ ASSERT3P(msp->ms_freeingtree, ==, NULL);
+ msp->ms_freeingtree = range_tree_create(NULL, msp,
+ &msp->ms_lock);
+
+ ASSERT3P(msp->ms_freedtree, ==, NULL);
+ msp->ms_freedtree = range_tree_create(NULL, msp,
+ &msp->ms_lock);
+
for (t = 0; t < TXG_DEFER_SIZE; t++) {
ASSERT(msp->ms_defertree[t] == NULL);
vdev_space_update(vd, 0, 0, msp->ms_size);
}
- freed_tree = &msp->ms_freetree[TXG_CLEAN(txg) & TXG_MASK];
defer_tree = &msp->ms_defertree[txg % TXG_DEFER_SIZE];
+ free_space = metaslab_class_get_space(spa_normal_class(spa)) -
+ metaslab_class_get_alloc(spa_normal_class(spa));
+ if (free_space <= spa_get_slop_space(spa)) {
+ defer_allowed = B_FALSE;
+ }
+
+ defer_delta = 0;
alloc_delta = space_map_alloc_delta(msp->ms_sm);
- defer_delta = range_tree_space(*freed_tree) -
- range_tree_space(*defer_tree);
+ if (defer_allowed) {
+ defer_delta = range_tree_space(msp->ms_freedtree) -
+ range_tree_space(*defer_tree);
+ } else {
+ defer_delta -= range_tree_space(*defer_tree);
+ }
vdev_space_update(vd, alloc_delta + defer_delta, defer_delta, 0);
- ASSERT0(range_tree_space(msp->ms_alloctree[txg & TXG_MASK]));
- ASSERT0(range_tree_space(msp->ms_freetree[txg & TXG_MASK]));
-
/*
* If there's a metaslab_load() in progress, wait for it to complete
* so that we have a consistent view of the in-core space map.
*/
range_tree_vacate(*defer_tree,
msp->ms_loaded ? range_tree_add : NULL, msp->ms_tree);
- range_tree_swap(freed_tree, defer_tree);
+ if (defer_allowed) {
+ range_tree_swap(&msp->ms_freedtree, defer_tree);
+ } else {
+ range_tree_vacate(msp->ms_freedtree,
+ msp->ms_loaded ? range_tree_add : NULL, msp->ms_tree);
+ }
space_map_update(msp->ms_sm);
vdev_dirty(vd, VDD_METASLAB, msp, txg + 1);
}
- if (msp->ms_loaded && msp->ms_access_txg < txg) {
+ /*
+ * Calculate the new weights before unloading any metaslabs.
+ * This will give us the most accurate weighting.
+ */
+ metaslab_group_sort(mg, msp, metaslab_weight(msp));
+
+ /*
+ * If the metaslab is loaded and we've not tried to load or allocate
+ * from it in 'metaslab_unload_delay' txgs, then unload it.
+ */
+ if (msp->ms_loaded &&
+ msp->ms_selected_txg + metaslab_unload_delay < txg) {
+
for (t = 1; t < TXG_CONCURRENT_STATES; t++) {
VERIFY0(range_tree_space(
msp->ms_alloctree[(txg + t) & TXG_MASK]));
metaslab_unload(msp);
}
- metaslab_group_sort(mg, msp, metaslab_weight(msp));
mutex_exit(&msp->ms_lock);
}
return (0);
}
+/*
+ * ==========================================================================
+ * Metaslab allocation tracing facility
+ * ==========================================================================
+ */
+#ifdef _METASLAB_TRACING
+kstat_t *metaslab_trace_ksp;
+kstat_named_t metaslab_trace_over_limit;
+
+void
+metaslab_alloc_trace_init(void)
+{
+ ASSERT(metaslab_alloc_trace_cache == NULL);
+ metaslab_alloc_trace_cache = kmem_cache_create(
+ "metaslab_alloc_trace_cache", sizeof (metaslab_alloc_trace_t),
+ 0, NULL, NULL, NULL, NULL, NULL, 0);
+ metaslab_trace_ksp = kstat_create("zfs", 0, "metaslab_trace_stats",
+ "misc", KSTAT_TYPE_NAMED, 1, KSTAT_FLAG_VIRTUAL);
+ if (metaslab_trace_ksp != NULL) {
+ metaslab_trace_ksp->ks_data = &metaslab_trace_over_limit;
+ kstat_named_init(&metaslab_trace_over_limit,
+ "metaslab_trace_over_limit", KSTAT_DATA_UINT64);
+ kstat_install(metaslab_trace_ksp);
+ }
+}
+
+void
+metaslab_alloc_trace_fini(void)
+{
+ if (metaslab_trace_ksp != NULL) {
+ kstat_delete(metaslab_trace_ksp);
+ metaslab_trace_ksp = NULL;
+ }
+ kmem_cache_destroy(metaslab_alloc_trace_cache);
+ metaslab_alloc_trace_cache = NULL;
+}
+
+/*
+ * Add an allocation trace element to the allocation tracing list.
+ */
+static void
+metaslab_trace_add(zio_alloc_list_t *zal, metaslab_group_t *mg,
+ metaslab_t *msp, uint64_t psize, uint32_t dva_id, uint64_t offset)
+{
+ metaslab_alloc_trace_t *mat;
+
+ if (!metaslab_trace_enabled)
+ return;
+
+ /*
+ * When the tracing list reaches its maximum we remove
+ * the second element in the list before adding a new one.
+ * By removing the second element we preserve the original
+ * entry as a clue to what allocations steps have already been
+ * performed.
+ */
+ if (zal->zal_size == metaslab_trace_max_entries) {
+ metaslab_alloc_trace_t *mat_next;
+#ifdef DEBUG
+ panic("too many entries in allocation list");
+#endif
+ atomic_inc_64(&metaslab_trace_over_limit.value.ui64);
+ zal->zal_size--;
+ mat_next = list_next(&zal->zal_list, list_head(&zal->zal_list));
+ list_remove(&zal->zal_list, mat_next);
+ kmem_cache_free(metaslab_alloc_trace_cache, mat_next);
+ }
+
+ mat = kmem_cache_alloc(metaslab_alloc_trace_cache, KM_SLEEP);
+ list_link_init(&mat->mat_list_node);
+ mat->mat_mg = mg;
+ mat->mat_msp = msp;
+ mat->mat_size = psize;
+ mat->mat_dva_id = dva_id;
+ mat->mat_offset = offset;
+ mat->mat_weight = 0;
+
+ if (msp != NULL)
+ mat->mat_weight = msp->ms_weight;
+
+ /*
+ * The list is part of the zio so locking is not required. Only
+ * a single thread will perform allocations for a given zio.
+ */
+ list_insert_tail(&zal->zal_list, mat);
+ zal->zal_size++;
+
+ ASSERT3U(zal->zal_size, <=, metaslab_trace_max_entries);
+}
+
+void
+metaslab_trace_init(zio_alloc_list_t *zal)
+{
+ list_create(&zal->zal_list, sizeof (metaslab_alloc_trace_t),
+ offsetof(metaslab_alloc_trace_t, mat_list_node));
+ zal->zal_size = 0;
+}
+
+void
+metaslab_trace_fini(zio_alloc_list_t *zal)
+{
+ metaslab_alloc_trace_t *mat;
+
+ while ((mat = list_remove_head(&zal->zal_list)) != NULL)
+ kmem_cache_free(metaslab_alloc_trace_cache, mat);
+ list_destroy(&zal->zal_list);
+ zal->zal_size = 0;
+}
+#else
+
+#define metaslab_trace_add(zal, mg, msp, psize, id, off)
+
+void
+metaslab_alloc_trace_init(void)
+{
+}
+
+void
+metaslab_alloc_trace_fini(void)
+{
+}
+
+void
+metaslab_trace_init(zio_alloc_list_t *zal)
+{
+}
+
+void
+metaslab_trace_fini(zio_alloc_list_t *zal)
+{
+}
+
+#endif /* _METASLAB_TRACING */
+
+/*
+ * ==========================================================================
+ * Metaslab block operations
+ * ==========================================================================
+ */
+
+static void
+metaslab_group_alloc_increment(spa_t *spa, uint64_t vdev, void *tag, int flags)
+{
+ metaslab_group_t *mg;
+
+ if (!(flags & METASLAB_ASYNC_ALLOC) ||
+ flags & METASLAB_DONT_THROTTLE)
+ return;
+
+ mg = vdev_lookup_top(spa, vdev)->vdev_mg;
+ if (!mg->mg_class->mc_alloc_throttle_enabled)
+ return;
+
+ (void) refcount_add(&mg->mg_alloc_queue_depth, tag);
+}
+
+void
+metaslab_group_alloc_decrement(spa_t *spa, uint64_t vdev, void *tag, int flags)
+{
+ metaslab_group_t *mg;
+
+ if (!(flags & METASLAB_ASYNC_ALLOC) ||
+ flags & METASLAB_DONT_THROTTLE)
+ return;
+
+ mg = vdev_lookup_top(spa, vdev)->vdev_mg;
+ if (!mg->mg_class->mc_alloc_throttle_enabled)
+ return;
+
+ (void) refcount_remove(&mg->mg_alloc_queue_depth, tag);
+}
+
+void
+metaslab_group_alloc_verify(spa_t *spa, const blkptr_t *bp, void *tag)
+{
+#ifdef ZFS_DEBUG
+ const dva_t *dva = bp->blk_dva;
+ int ndvas = BP_GET_NDVAS(bp);
+ int d;
+
+ for (d = 0; d < ndvas; d++) {
+ uint64_t vdev = DVA_GET_VDEV(&dva[d]);
+ metaslab_group_t *mg = vdev_lookup_top(spa, vdev)->vdev_mg;
+ VERIFY(refcount_not_held(&mg->mg_alloc_queue_depth, tag));
+ }
+#endif
+}
+
static uint64_t
-metaslab_group_alloc(metaslab_group_t *mg, uint64_t psize, uint64_t asize,
- uint64_t txg, uint64_t min_distance, dva_t *dva, int d)
+metaslab_block_alloc(metaslab_t *msp, uint64_t size, uint64_t txg)
+{
+ uint64_t start;
+ range_tree_t *rt = msp->ms_tree;
+ metaslab_class_t *mc = msp->ms_group->mg_class;
+
+ VERIFY(!msp->ms_condensing);
+
+ start = mc->mc_ops->msop_alloc(msp, size);
+ if (start != -1ULL) {
+ metaslab_group_t *mg = msp->ms_group;
+ vdev_t *vd = mg->mg_vd;
+
+ VERIFY0(P2PHASE(start, 1ULL << vd->vdev_ashift));
+ VERIFY0(P2PHASE(size, 1ULL << vd->vdev_ashift));
+ VERIFY3U(range_tree_space(rt) - size, <=, msp->ms_size);
+ range_tree_remove(rt, start, size);
+
+ if (range_tree_space(msp->ms_alloctree[txg & TXG_MASK]) == 0)
+ vdev_dirty(mg->mg_vd, VDD_METASLAB, msp, txg);
+
+ range_tree_add(msp->ms_alloctree[txg & TXG_MASK], start, size);
+
+ /* Track the last successful allocation */
+ msp->ms_alloc_txg = txg;
+ metaslab_verify_space(msp, txg);
+ }
+
+ /*
+ * Now that we've attempted the allocation we need to update the
+ * metaslab's maximum block size since it may have changed.
+ */
+ msp->ms_max_size = metaslab_block_maxsize(msp);
+ return (start);
+}
+
+static uint64_t
+metaslab_group_alloc_normal(metaslab_group_t *mg, zio_alloc_list_t *zal,
+ uint64_t asize, uint64_t txg, uint64_t min_distance, dva_t *dva, int d)
{
- spa_t *spa = mg->mg_vd->vdev_spa;
metaslab_t *msp = NULL;
+ metaslab_t *search;
uint64_t offset = -1ULL;
- avl_tree_t *t = &mg->mg_metaslab_tree;
uint64_t activation_weight;
uint64_t target_distance;
int i;
}
}
+ search = kmem_alloc(sizeof (*search), KM_SLEEP);
+ search->ms_weight = UINT64_MAX;
+ search->ms_start = 0;
for (;;) {
boolean_t was_active;
+ avl_tree_t *t = &mg->mg_metaslab_tree;
+ avl_index_t idx;
mutex_enter(&mg->mg_lock);
- for (msp = avl_first(t); msp; msp = AVL_NEXT(t, msp)) {
- if (msp->ms_weight < asize) {
- spa_dbgmsg(spa, "%s: failed to meet weight "
- "requirement: vdev %llu, txg %llu, mg %p, "
- "msp %p, psize %llu, asize %llu, "
- "weight %llu", spa_name(spa),
- mg->mg_vd->vdev_id, txg,
- mg, msp, psize, asize, msp->ms_weight);
- mutex_exit(&mg->mg_lock);
- return (-1ULL);
+
+ /*
+ * Find the metaslab with the highest weight that is less
+ * than what we've already tried. In the common case, this
+ * means that we will examine each metaslab at most once.
+ * Note that concurrent callers could reorder metaslabs
+ * by activation/passivation once we have dropped the mg_lock.
+ * If a metaslab is activated by another thread, and we fail
+ * to allocate from the metaslab we have selected, we may
+ * not try the newly-activated metaslab, and instead activate
+ * another metaslab. This is not optimal, but generally
+ * does not cause any problems (a possible exception being
+ * if every metaslab is completely full except for the
+ * the newly-activated metaslab which we fail to examine).
+ */
+ msp = avl_find(t, search, &idx);
+ if (msp == NULL)
+ msp = avl_nearest(t, idx, AVL_AFTER);
+ for (; msp != NULL; msp = AVL_NEXT(t, msp)) {
+
+ if (!metaslab_should_allocate(msp, asize)) {
+ metaslab_trace_add(zal, mg, msp, asize, d,
+ TRACE_TOO_SMALL);
+ continue;
}
/*
(space_map_allocated(msp->ms_sm) != 0 ? 0 :
min_distance >> 1);
- for (i = 0; i < d; i++)
+ for (i = 0; i < d; i++) {
if (metaslab_distance(msp, &dva[i]) <
target_distance)
break;
+ }
if (i == d)
break;
}
mutex_exit(&mg->mg_lock);
- if (msp == NULL)
+ if (msp == NULL) {
+ kmem_free(search, sizeof (*search));
return (-1ULL);
+ }
+ search->ms_weight = msp->ms_weight;
+ search->ms_start = msp->ms_start + 1;
mutex_enter(&msp->ms_lock);
* Ensure that the metaslab we have selected is still
* capable of handling our request. It's possible that
* another thread may have changed the weight while we
- * were blocked on the metaslab lock.
+ * were blocked on the metaslab lock. We check the
+ * active status first to see if we need to reselect
+ * a new metaslab.
*/
- if (msp->ms_weight < asize || (was_active &&
- !(msp->ms_weight & METASLAB_ACTIVE_MASK) &&
- activation_weight == METASLAB_WEIGHT_PRIMARY)) {
+ if (was_active && !(msp->ms_weight & METASLAB_ACTIVE_MASK)) {
mutex_exit(&msp->ms_lock);
continue;
}
mutex_exit(&msp->ms_lock);
continue;
}
+ msp->ms_selected_txg = txg;
+
+ /*
+ * Now that we have the lock, recheck to see if we should
+ * continue to use this metaslab for this allocation. The
+ * the metaslab is now loaded so metaslab_should_allocate() can
+ * accurately determine if the allocation attempt should
+ * proceed.
+ */
+ if (!metaslab_should_allocate(msp, asize)) {
+ /* Passivate this metaslab and select a new one. */
+ metaslab_trace_add(zal, mg, msp, asize, d,
+ TRACE_TOO_SMALL);
+ goto next;
+ }
+
/*
* If this metaslab is currently condensing then pick again as
* to disk.
*/
if (msp->ms_condensing) {
+ metaslab_trace_add(zal, mg, msp, asize, d,
+ TRACE_CONDENSING);
mutex_exit(&msp->ms_lock);
continue;
}
- if ((offset = metaslab_block_alloc(msp, asize)) != -1ULL)
+ offset = metaslab_block_alloc(msp, asize, txg);
+ metaslab_trace_add(zal, mg, msp, asize, d, offset);
+
+ if (offset != -1ULL) {
+ /* Proactively passivate the metaslab, if needed */
+ metaslab_segment_may_passivate(msp);
break;
+ }
+next:
+ ASSERT(msp->ms_loaded);
- metaslab_passivate(msp, metaslab_block_maxsize(msp));
+ /*
+ * We were unable to allocate from this metaslab so determine
+ * a new weight for this metaslab. Now that we have loaded
+ * the metaslab we can provide a better hint to the metaslab
+ * selector.
+ *
+ * For space-based metaslabs, we use the maximum block size.
+ * This information is only available when the metaslab
+ * is loaded and is more accurate than the generic free
+ * space weight that was calculated by metaslab_weight().
+ * This information allows us to quickly compare the maximum
+ * available allocation in the metaslab to the allocation
+ * size being requested.
+ *
+ * For segment-based metaslabs, determine the new weight
+ * based on the highest bucket in the range tree. We
+ * explicitly use the loaded segment weight (i.e. the range
+ * tree histogram) since it contains the space that is
+ * currently available for allocation and is accurate
+ * even within a sync pass.
+ */
+ if (WEIGHT_IS_SPACEBASED(msp->ms_weight)) {
+ uint64_t weight = metaslab_block_maxsize(msp);
+ WEIGHT_SET_SPACEBASED(weight);
+ metaslab_passivate(msp, weight);
+ } else {
+ metaslab_passivate(msp,
+ metaslab_weight_from_range_tree(msp));
+ }
+
+ /*
+ * We have just failed an allocation attempt, check
+ * that metaslab_should_allocate() agrees. Otherwise,
+ * we may end up in an infinite loop retrying the same
+ * metaslab.
+ */
+ ASSERT(!metaslab_should_allocate(msp, asize));
mutex_exit(&msp->ms_lock);
}
+ mutex_exit(&msp->ms_lock);
+ kmem_free(search, sizeof (*search));
+ return (offset);
+}
- if (range_tree_space(msp->ms_alloctree[txg & TXG_MASK]) == 0)
- vdev_dirty(mg->mg_vd, VDD_METASLAB, msp, txg);
-
- range_tree_add(msp->ms_alloctree[txg & TXG_MASK], offset, asize);
- msp->ms_access_txg = txg + metaslab_unload_delay;
+static uint64_t
+metaslab_group_alloc(metaslab_group_t *mg, zio_alloc_list_t *zal,
+ uint64_t asize, uint64_t txg, uint64_t min_distance, dva_t *dva, int d)
+{
+ uint64_t offset;
+ ASSERT(mg->mg_initialized);
- mutex_exit(&msp->ms_lock);
+ offset = metaslab_group_alloc_normal(mg, zal, asize, txg,
+ min_distance, dva, d);
+ mutex_enter(&mg->mg_lock);
+ if (offset == -1ULL) {
+ mg->mg_failed_allocations++;
+ metaslab_trace_add(zal, mg, NULL, asize, d,
+ TRACE_GROUP_FAILURE);
+ if (asize == SPA_GANGBLOCKSIZE) {
+ /*
+ * This metaslab group was unable to allocate
+ * the minimum gang block size so it must be out of
+ * space. We must notify the allocation throttle
+ * to start skipping allocation attempts to this
+ * metaslab group until more space becomes available.
+ * Note: this failure cannot be caused by the
+ * allocation throttle since the allocation throttle
+ * is only responsible for skipping devices and
+ * not failing block allocations.
+ */
+ mg->mg_no_free_space = B_TRUE;
+ }
+ }
+ mg->mg_allocations++;
+ mutex_exit(&mg->mg_lock);
return (offset);
}
+/*
+ * If we have to write a ditto block (i.e. more than one DVA for a given BP)
+ * on the same vdev as an existing DVA of this BP, then try to allocate it
+ * at least (vdev_asize / (2 ^ ditto_same_vdev_distance_shift)) away from the
+ * existing DVAs.
+ */
+int ditto_same_vdev_distance_shift = 3;
+
/*
* Allocate a block for the specified i/o.
*/
static int
metaslab_alloc_dva(spa_t *spa, metaslab_class_t *mc, uint64_t psize,
- dva_t *dva, int d, dva_t *hintdva, uint64_t txg, int flags)
+ dva_t *dva, int d, dva_t *hintdva, uint64_t txg, int flags,
+ zio_alloc_list_t *zal)
{
metaslab_group_t *mg, *fast_mg, *rotor;
vdev_t *vd;
- int dshift = 3;
- int all_zero;
- int zio_lock = B_FALSE;
- boolean_t allocatable;
- uint64_t offset = -1ULL;
- uint64_t asize;
- uint64_t distance;
+ boolean_t try_hard = B_FALSE;
ASSERT(!DVA_IS_VALID(&dva[d]));
/*
* For testing, make some blocks above a certain size be gang blocks.
*/
- if (psize >= metaslab_gang_bang && (ddi_get_lbolt() & 3) == 0)
+ if (psize >= metaslab_gang_bang && (ddi_get_lbolt() & 3) == 0) {
+ metaslab_trace_add(zal, NULL, NULL, psize, d, TRACE_FORCE_GANG);
return (SET_ERROR(ENOSPC));
-
- if (flags & METASLAB_FASTWRITE)
- mutex_enter(&mc->mc_fastwrite_lock);
+ }
/*
* Start at the rotor and loop through all mgs until we find something.
rotor = mg;
top:
- all_zero = B_TRUE;
do {
- ASSERT(mg->mg_activation_count == 1);
+ boolean_t allocatable;
+ uint64_t offset;
+ uint64_t distance, asize;
+ ASSERT(mg->mg_activation_count == 1);
vd = mg->mg_vd;
/*
* Don't allocate from faulted devices.
*/
- if (zio_lock) {
+ if (try_hard) {
spa_config_enter(spa, SCL_ZIO, FTAG, RW_READER);
allocatable = vdev_allocatable(vd);
spa_config_exit(spa, SCL_ZIO, FTAG);
/*
* Determine if the selected metaslab group is eligible
- * for allocations. If we're ganging or have requested
- * an allocation for the smallest gang block size
- * then we don't want to avoid allocating to the this
- * metaslab group. If we're in this condition we should
- * try to allocate from any device possible so that we
- * don't inadvertently return ENOSPC and suspend the pool
+ * for allocations. If we're ganging then don't allow
+ * this metaslab group to skip allocations since that would
+ * inadvertently return ENOSPC and suspend the pool
* even though space is still available.
*/
- if (allocatable && CAN_FASTGANG(flags) &&
- psize > SPA_GANGBLOCKSIZE)
- allocatable = metaslab_group_allocatable(mg);
+ if (allocatable && !GANG_ALLOCATION(flags) && !try_hard) {
+ allocatable = metaslab_group_allocatable(mg, rotor,
+ psize);
+ }
- if (!allocatable)
+ if (!allocatable) {
+ metaslab_trace_add(zal, mg, NULL, psize, d,
+ TRACE_NOT_ALLOCATABLE);
goto next;
+ }
+
+ ASSERT(mg->mg_initialized);
/*
- * Avoid writing single-copy data to a failing vdev
- * unless the user instructs us that it is okay.
+ * Avoid writing single-copy data to a failing,
+ * non-redundant vdev, unless we've already tried all
+ * other vdevs.
*/
if ((vd->vdev_stat.vs_write_errors > 0 ||
vd->vdev_state < VDEV_STATE_HEALTHY) &&
- d == 0 && dshift == 3 && vd->vdev_children == 0) {
- all_zero = B_FALSE;
+ d == 0 && !try_hard && vd->vdev_children == 0) {
+ metaslab_trace_add(zal, mg, NULL, psize, d,
+ TRACE_VDEV_ERROR);
goto next;
}
ASSERT(mg->mg_class == mc);
- distance = vd->vdev_asize >> dshift;
- if (distance <= (1ULL << vd->vdev_ms_shift))
- distance = 0;
- else
- all_zero = B_FALSE;
+ /*
+ * If we don't need to try hard, then require that the
+ * block be 1/8th of the device away from any other DVAs
+ * in this BP. If we are trying hard, allow any offset
+ * to be used (distance=0).
+ */
+ distance = 0;
+ if (!try_hard) {
+ distance = vd->vdev_asize >>
+ ditto_same_vdev_distance_shift;
+ if (distance <= (1ULL << vd->vdev_ms_shift))
+ distance = 0;
+ }
asize = vdev_psize_to_asize(vd, psize);
ASSERT(P2PHASE(asize, 1ULL << vd->vdev_ashift) == 0);
- offset = metaslab_group_alloc(mg, psize, asize, txg, distance,
+ offset = metaslab_group_alloc(mg, zal, asize, txg, distance,
dva, d);
+
if (offset != -1ULL) {
/*
* If we've just selected this metaslab group,
DVA_SET_VDEV(&dva[d], vd->vdev_id);
DVA_SET_OFFSET(&dva[d], offset);
- DVA_SET_GANG(&dva[d], !!(flags & METASLAB_GANG_HEADER));
+ DVA_SET_GANG(&dva[d],
+ ((flags & METASLAB_GANG_HEADER) ? 1 : 0));
DVA_SET_ASIZE(&dva[d], asize);
if (flags & METASLAB_FASTWRITE) {
atomic_add_64(&vd->vdev_pending_fastwrite,
psize);
- mutex_exit(&mc->mc_fastwrite_lock);
}
return (0);
mc->mc_aliquot = 0;
} while ((mg = mg->mg_next) != rotor);
- if (!all_zero) {
- dshift++;
- ASSERT(dshift < 64);
- goto top;
- }
-
- if (!allocatable && !zio_lock) {
- dshift = 3;
- zio_lock = B_TRUE;
+ /*
+ * If we haven't tried hard, do so now.
+ */
+ if (!try_hard) {
+ try_hard = B_TRUE;
goto top;
}
bzero(&dva[d], sizeof (dva_t));
- if (flags & METASLAB_FASTWRITE)
- mutex_exit(&mc->mc_fastwrite_lock);
-
+ metaslab_trace_add(zal, rotor, NULL, psize, d, TRACE_ENOSPC);
return (SET_ERROR(ENOSPC));
}
VERIFY0(P2PHASE(offset, 1ULL << vd->vdev_ashift));
VERIFY0(P2PHASE(size, 1ULL << vd->vdev_ashift));
range_tree_add(msp->ms_tree, offset, size);
+ msp->ms_max_size = metaslab_block_maxsize(msp);
} else {
- if (range_tree_space(msp->ms_freetree[txg & TXG_MASK]) == 0)
+ VERIFY3U(txg, ==, spa->spa_syncing_txg);
+ if (range_tree_space(msp->ms_freeingtree) == 0)
vdev_dirty(vd, VDD_METASLAB, msp, txg);
- range_tree_add(msp->ms_freetree[txg & TXG_MASK],
- offset, size);
+ range_tree_add(msp->ms_freeingtree, offset, size);
}
mutex_exit(&msp->ms_lock);
return (0);
}
+/*
+ * Reserve some allocation slots. The reservation system must be called
+ * before we call into the allocator. If there aren't any available slots
+ * then the I/O will be throttled until an I/O completes and its slots are
+ * freed up. The function returns true if it was successful in placing
+ * the reservation.
+ */
+boolean_t
+metaslab_class_throttle_reserve(metaslab_class_t *mc, int slots, zio_t *zio,
+ int flags)
+{
+ uint64_t available_slots = 0;
+ uint64_t reserved_slots;
+ boolean_t slot_reserved = B_FALSE;
+
+ ASSERT(mc->mc_alloc_throttle_enabled);
+ mutex_enter(&mc->mc_lock);
+
+ reserved_slots = refcount_count(&mc->mc_alloc_slots);
+ if (reserved_slots < mc->mc_alloc_max_slots)
+ available_slots = mc->mc_alloc_max_slots - reserved_slots;
+
+ if (slots <= available_slots || GANG_ALLOCATION(flags)) {
+ int d;
+
+ /*
+ * We reserve the slots individually so that we can unreserve
+ * them individually when an I/O completes.
+ */
+ for (d = 0; d < slots; d++) {
+ reserved_slots = refcount_add(&mc->mc_alloc_slots, zio);
+ }
+ zio->io_flags |= ZIO_FLAG_IO_ALLOCATING;
+ slot_reserved = B_TRUE;
+ }
+
+ mutex_exit(&mc->mc_lock);
+ return (slot_reserved);
+}
+
+void
+metaslab_class_throttle_unreserve(metaslab_class_t *mc, int slots, zio_t *zio)
+{
+ int d;
+
+ ASSERT(mc->mc_alloc_throttle_enabled);
+ mutex_enter(&mc->mc_lock);
+ for (d = 0; d < slots; d++) {
+ (void) refcount_remove(&mc->mc_alloc_slots, zio);
+ }
+ mutex_exit(&mc->mc_lock);
+}
+
int
metaslab_alloc(spa_t *spa, metaslab_class_t *mc, uint64_t psize, blkptr_t *bp,
- int ndvas, uint64_t txg, blkptr_t *hintbp, int flags)
+ int ndvas, uint64_t txg, blkptr_t *hintbp, int flags,
+ zio_alloc_list_t *zal, zio_t *zio)
{
dva_t *dva = bp->blk_dva;
dva_t *hintdva = hintbp->blk_dva;
ASSERT(ndvas > 0 && ndvas <= spa_max_replication(spa));
ASSERT(BP_GET_NDVAS(bp) == 0);
ASSERT(hintbp == NULL || ndvas <= BP_GET_NDVAS(hintbp));
+ ASSERT3P(zal, !=, NULL);
for (d = 0; d < ndvas; d++) {
error = metaslab_alloc_dva(spa, mc, psize, dva, d, hintdva,
- txg, flags);
+ txg, flags, zal);
if (error != 0) {
for (d--; d >= 0; d--) {
metaslab_free_dva(spa, &dva[d], txg, B_TRUE);
+ metaslab_group_alloc_decrement(spa,
+ DVA_GET_VDEV(&dva[d]), zio, flags);
bzero(&dva[d], sizeof (dva_t));
}
spa_config_exit(spa, SCL_ALLOC, FTAG);
return (error);
+ } else {
+ /*
+ * Update the metaslab group's queue depth
+ * based on the newly allocated dva.
+ */
+ metaslab_group_alloc_increment(spa,
+ DVA_GET_VDEV(&dva[d]), zio, flags);
}
+
}
ASSERT(error == 0);
ASSERT(BP_GET_NDVAS(bp) == ndvas);
spa_config_exit(spa, SCL_ALLOC, FTAG);
- BP_SET_BIRTH(bp, txg, txg);
+ BP_SET_BIRTH(bp, txg, 0);
return (0);
}
if (msp->ms_loaded)
range_tree_verify(msp->ms_tree, offset, size);
- for (j = 0; j < TXG_SIZE; j++)
- range_tree_verify(msp->ms_freetree[j], offset, size);
+ range_tree_verify(msp->ms_freeingtree, offset, size);
+ range_tree_verify(msp->ms_freedtree, offset, size);
for (j = 0; j < TXG_DEFER_SIZE; j++)
range_tree_verify(msp->ms_defertree[j], offset, size);
}
}
#if defined(_KERNEL) && defined(HAVE_SPL)
+/* CSTYLED */
module_param(metaslab_aliquot, ulong, 0644);
-module_param(metaslab_debug_load, int, 0644);
-module_param(metaslab_debug_unload, int, 0644);
-module_param(metaslab_preload_enabled, int, 0644);
-module_param(zfs_mg_noalloc_threshold, int, 0644);
-module_param(zfs_mg_fragmentation_threshold, int, 0644);
-module_param(zfs_metaslab_fragmentation_threshold, int, 0644);
-module_param(metaslab_fragmentation_factor_enabled, int, 0644);
-module_param(metaslab_lba_weighting_enabled, int, 0644);
-module_param(metaslab_bias_enabled, int, 0644);
-
MODULE_PARM_DESC(metaslab_aliquot,
"allocation granularity (a.k.a. stripe size)");
+
+module_param(metaslab_debug_load, int, 0644);
MODULE_PARM_DESC(metaslab_debug_load,
"load all metaslabs when pool is first opened");
+
+module_param(metaslab_debug_unload, int, 0644);
MODULE_PARM_DESC(metaslab_debug_unload,
"prevent metaslabs from being unloaded");
+
+module_param(metaslab_preload_enabled, int, 0644);
MODULE_PARM_DESC(metaslab_preload_enabled,
"preload potential metaslabs during reassessment");
+module_param(zfs_mg_noalloc_threshold, int, 0644);
MODULE_PARM_DESC(zfs_mg_noalloc_threshold,
"percentage of free space for metaslab group to allow allocation");
+
+module_param(zfs_mg_fragmentation_threshold, int, 0644);
MODULE_PARM_DESC(zfs_mg_fragmentation_threshold,
"fragmentation for metaslab group to allow allocation");
+module_param(zfs_metaslab_fragmentation_threshold, int, 0644);
MODULE_PARM_DESC(zfs_metaslab_fragmentation_threshold,
"fragmentation for metaslab to allow allocation");
+
+module_param(metaslab_fragmentation_factor_enabled, int, 0644);
MODULE_PARM_DESC(metaslab_fragmentation_factor_enabled,
"use the fragmentation metric to prefer less fragmented metaslabs");
+
+module_param(metaslab_lba_weighting_enabled, int, 0644);
MODULE_PARM_DESC(metaslab_lba_weighting_enabled,
"prefer metaslabs with lower LBAs");
+
+module_param(metaslab_bias_enabled, int, 0644);
MODULE_PARM_DESC(metaslab_bias_enabled,
"enable metaslab group biasing");
+
+module_param(zfs_metaslab_segment_weight_enabled, int, 0644);
+MODULE_PARM_DESC(zfs_metaslab_segment_weight_enabled,
+ "enable segment-based metaslab selection");
+
+module_param(zfs_metaslab_switch_threshold, int, 0644);
+MODULE_PARM_DESC(zfs_metaslab_switch_threshold,
+ "segment-based metaslab selection maximum buckets before switching");
#endif /* _KERNEL && HAVE_SPL */
projects / mirror_ubuntu-bionic-kernel.git / blobdiff