* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
- * or http://www.opensolaris.org/os/licensing.
+ * or https://opensource.org/licenses/CDDL-1.0.
* See the License for the specific language governing permissions
* and limitations under the License.
*
*/
/*
- * Copyright (c) 2012 by Delphix. All rights reserved.
+ * Copyright (c) 2012, 2015 by Delphix. All rights reserved.
*/
#include <sys/zfs_context.h>
#include <sys/spa.h>
+#include <sys/spa_impl.h>
+#include <sys/dsl_pool.h>
+#include <sys/dsl_scan.h>
#include <sys/vdev_impl.h>
+#include <sys/vdev_draid.h>
#include <sys/zio.h>
+#include <sys/zio_checksum.h>
+#include <sys/abd.h>
#include <sys/fs/zfs.h>
/*
- * Virtual device vector for mirroring.
+ * Vdev mirror kstats
*/
+static kstat_t *mirror_ksp = NULL;
+
+typedef struct mirror_stats {
+ kstat_named_t vdev_mirror_stat_rotating_linear;
+ kstat_named_t vdev_mirror_stat_rotating_offset;
+ kstat_named_t vdev_mirror_stat_rotating_seek;
+ kstat_named_t vdev_mirror_stat_non_rotating_linear;
+ kstat_named_t vdev_mirror_stat_non_rotating_seek;
+
+ kstat_named_t vdev_mirror_stat_preferred_found;
+ kstat_named_t vdev_mirror_stat_preferred_not_found;
+} mirror_stats_t;
+
+static mirror_stats_t mirror_stats = {
+ /* New I/O follows directly the last I/O */
+ { "rotating_linear", KSTAT_DATA_UINT64 },
+ /* New I/O is within zfs_vdev_mirror_rotating_seek_offset of the last */
+ { "rotating_offset", KSTAT_DATA_UINT64 },
+ /* New I/O requires random seek */
+ { "rotating_seek", KSTAT_DATA_UINT64 },
+ /* New I/O follows directly the last I/O (nonrot) */
+ { "non_rotating_linear", KSTAT_DATA_UINT64 },
+ /* New I/O requires random seek (nonrot) */
+ { "non_rotating_seek", KSTAT_DATA_UINT64 },
+ /* Preferred child vdev found */
+ { "preferred_found", KSTAT_DATA_UINT64 },
+ /* Preferred child vdev not found or equal load */
+ { "preferred_not_found", KSTAT_DATA_UINT64 },
+
+};
+
+#define MIRROR_STAT(stat) (mirror_stats.stat.value.ui64)
+#define MIRROR_INCR(stat, val) atomic_add_64(&MIRROR_STAT(stat), val)
+#define MIRROR_BUMP(stat) MIRROR_INCR(stat, 1)
+
+void
+vdev_mirror_stat_init(void)
+{
+ mirror_ksp = kstat_create("zfs", 0, "vdev_mirror_stats",
+ "misc", KSTAT_TYPE_NAMED,
+ sizeof (mirror_stats) / sizeof (kstat_named_t), KSTAT_FLAG_VIRTUAL);
+ if (mirror_ksp != NULL) {
+ mirror_ksp->ks_data = &mirror_stats;
+ kstat_install(mirror_ksp);
+ }
+}
+void
+vdev_mirror_stat_fini(void)
+{
+ if (mirror_ksp != NULL) {
+ kstat_delete(mirror_ksp);
+ mirror_ksp = NULL;
+ }
+}
+
+/*
+ * Virtual device vector for mirroring.
+ */
typedef struct mirror_child {
vdev_t *mc_vd;
+ abd_t *mc_abd;
uint64_t mc_offset;
int mc_error;
- int mc_pending;
+ int mc_load;
uint8_t mc_tried;
uint8_t mc_skipped;
uint8_t mc_speculative;
+ uint8_t mc_rebuilding;
} mirror_child_t;
typedef struct mirror_map {
+ int *mm_preferred;
+ int mm_preferred_cnt;
int mm_children;
- int mm_replacing;
- int mm_preferred;
- int mm_root;
- mirror_child_t mm_child[1];
+ boolean_t mm_resilvering;
+ boolean_t mm_rebuilding;
+ boolean_t mm_root;
+ mirror_child_t mm_child[];
} mirror_map_t;
+static const int vdev_mirror_shift = 21;
+
/*
- * When the children are equally busy queue incoming requests to a single
- * child for N microseconds. This is done to maximize the likelihood that
- * the Linux elevator will be able to merge requests while it is plugged.
- * Otherwise, requests are queued to the least busy device.
+ * The load configuration settings below are tuned by default for
+ * the case where all devices are of the same rotational type.
*
- * For rotational disks the Linux elevator will plug for 10ms which is
- * why zfs_vdev_mirror_switch_us is set to 10ms by default. For non-
- * rotational disks the elevator will not plug, but 10ms is still a small
- * enough value that the requests will get spread over all the children.
- *
- * For fast SSDs it may make sense to decrease zfs_vdev_mirror_switch_us
- * significantly to bound the worst case latencies. It would probably be
- * ideal to calculate a decaying average of the last observed latencies and
- * use that to dynamically adjust the zfs_vdev_mirror_switch_us time.
+ * If there is a mixture of rotating and non-rotating media, setting
+ * zfs_vdev_mirror_non_rotating_seek_inc to 0 may well provide better results
+ * as it will direct more reads to the non-rotating vdevs which are more likely
+ * to have a higher performance.
*/
-int zfs_vdev_mirror_switch_us = 10000;
+
+/* Rotating media load calculation configuration. */
+static int zfs_vdev_mirror_rotating_inc = 0;
+static int zfs_vdev_mirror_rotating_seek_inc = 5;
+static int zfs_vdev_mirror_rotating_seek_offset = 1 * 1024 * 1024;
+
+/* Non-rotating media load calculation configuration. */
+static int zfs_vdev_mirror_non_rotating_inc = 0;
+static int zfs_vdev_mirror_non_rotating_seek_inc = 1;
+
+static inline size_t
+vdev_mirror_map_size(int children)
+{
+ return (offsetof(mirror_map_t, mm_child[children]) +
+ sizeof (int) * children);
+}
+
+static inline mirror_map_t *
+vdev_mirror_map_alloc(int children, boolean_t resilvering, boolean_t root)
+{
+ mirror_map_t *mm;
+
+ mm = kmem_zalloc(vdev_mirror_map_size(children), KM_SLEEP);
+ mm->mm_children = children;
+ mm->mm_resilvering = resilvering;
+ mm->mm_root = root;
+ mm->mm_preferred = (int *)((uintptr_t)mm +
+ offsetof(mirror_map_t, mm_child[children]));
+
+ return (mm);
+}
static void
vdev_mirror_map_free(zio_t *zio)
{
mirror_map_t *mm = zio->io_vsd;
- kmem_free(mm, offsetof(mirror_map_t, mm_child[mm->mm_children]));
+ kmem_free(mm, vdev_mirror_map_size(mm->mm_children));
}
static const zio_vsd_ops_t vdev_mirror_vsd_ops = {
- vdev_mirror_map_free,
- zio_vsd_default_cksum_report
+ .vsd_free = vdev_mirror_map_free,
};
static int
-vdev_mirror_pending(vdev_t *vd)
+vdev_mirror_load(mirror_map_t *mm, vdev_t *vd, uint64_t zio_offset)
{
- vdev_queue_t *vq = &vd->vdev_queue;
- int pending;
+ uint64_t last_offset;
+ int64_t offset_diff;
+ int load;
+
+ /* All DVAs have equal weight at the root. */
+ if (mm->mm_root)
+ return (INT_MAX);
+
+ /*
+ * We don't return INT_MAX if the device is resilvering i.e.
+ * vdev_resilver_txg != 0 as when tested performance was slightly
+ * worse overall when resilvering with compared to without.
+ */
+
+ /* Fix zio_offset for leaf vdevs */
+ if (vd->vdev_ops->vdev_op_leaf)
+ zio_offset += VDEV_LABEL_START_SIZE;
+
+ /* Standard load based on pending queue length. */
+ load = vdev_queue_length(vd);
+ last_offset = vdev_queue_last_offset(vd);
+
+ if (vd->vdev_nonrot) {
+ /* Non-rotating media. */
+ if (last_offset == zio_offset) {
+ MIRROR_BUMP(vdev_mirror_stat_non_rotating_linear);
+ return (load + zfs_vdev_mirror_non_rotating_inc);
+ }
+
+ /*
+ * Apply a seek penalty even for non-rotating devices as
+ * sequential I/O's can be aggregated into fewer operations on
+ * the device, thus avoiding unnecessary per-command overhead
+ * and boosting performance.
+ */
+ MIRROR_BUMP(vdev_mirror_stat_non_rotating_seek);
+ return (load + zfs_vdev_mirror_non_rotating_seek_inc);
+ }
- mutex_enter(&vq->vq_lock);
- pending = avl_numnodes(&vq->vq_pending_tree);
- mutex_exit(&vq->vq_lock);
+ /* Rotating media I/O's which directly follow the last I/O. */
+ if (last_offset == zio_offset) {
+ MIRROR_BUMP(vdev_mirror_stat_rotating_linear);
+ return (load + zfs_vdev_mirror_rotating_inc);
+ }
- return (pending);
+ /*
+ * Apply half the seek increment to I/O's within seek offset
+ * of the last I/O issued to this vdev as they should incur less
+ * of a seek increment.
+ */
+ offset_diff = (int64_t)(last_offset - zio_offset);
+ if (ABS(offset_diff) < zfs_vdev_mirror_rotating_seek_offset) {
+ MIRROR_BUMP(vdev_mirror_stat_rotating_offset);
+ return (load + (zfs_vdev_mirror_rotating_seek_inc / 2));
+ }
+
+ /* Apply the full seek increment to all other I/O's. */
+ MIRROR_BUMP(vdev_mirror_stat_rotating_seek);
+ return (load + zfs_vdev_mirror_rotating_seek_inc);
}
-static mirror_map_t *
-vdev_mirror_map_alloc(zio_t *zio)
+static boolean_t
+vdev_mirror_rebuilding(vdev_t *vd)
+{
+ if (vd->vdev_ops->vdev_op_leaf && vd->vdev_rebuild_txg)
+ return (B_TRUE);
+
+ for (int i = 0; i < vd->vdev_children; i++) {
+ if (vdev_mirror_rebuilding(vd->vdev_child[i])) {
+ return (B_TRUE);
+ }
+ }
+
+ return (B_FALSE);
+}
+
+/*
+ * Avoid inlining the function to keep vdev_mirror_io_start(), which
+ * is this functions only caller, as small as possible on the stack.
+ */
+noinline static mirror_map_t *
+vdev_mirror_map_init(zio_t *zio)
{
mirror_map_t *mm = NULL;
mirror_child_t *mc;
vdev_t *vd = zio->io_vd;
- int c, d;
+ int c;
if (vd == NULL) {
dva_t *dva = zio->io_bp->blk_dva;
spa_t *spa = zio->io_spa;
+ dsl_scan_t *scn = spa->spa_dsl_pool->dp_scan;
+ dva_t dva_copy[SPA_DVAS_PER_BP];
- c = BP_GET_NDVAS(zio->io_bp);
-
- mm = kmem_zalloc(offsetof(mirror_map_t, mm_child[c]), KM_PUSHPAGE);
- mm->mm_children = c;
- mm->mm_replacing = B_FALSE;
- mm->mm_preferred = spa_get_random(c);
- mm->mm_root = B_TRUE;
+ /*
+ * The sequential scrub code sorts and issues all DVAs
+ * of a bp separately. Each of these IOs includes all
+ * original DVA copies so that repairs can be performed
+ * in the event of an error, but we only actually want
+ * to check the first DVA since the others will be
+ * checked by their respective sorted IOs. Only if we
+ * hit an error will we try all DVAs upon retrying.
+ *
+ * Note: This check is safe even if the user switches
+ * from a legacy scrub to a sequential one in the middle
+ * of processing, since scn_is_sorted isn't updated until
+ * all outstanding IOs from the previous scrub pass
+ * complete.
+ */
+ if ((zio->io_flags & ZIO_FLAG_SCRUB) &&
+ !(zio->io_flags & ZIO_FLAG_IO_RETRY) &&
+ dsl_scan_scrubbing(spa->spa_dsl_pool) &&
+ scn->scn_is_sorted) {
+ c = 1;
+ } else {
+ c = BP_GET_NDVAS(zio->io_bp);
+ }
/*
- * Check the other, lower-index DVAs to see if they're on
- * the same vdev as the child we picked. If they are, use
- * them since they are likely to have been allocated from
- * the primary metaslab in use at the time, and hence are
- * more likely to have locality with single-copy data.
+ * If the pool cannot be written to, then infer that some
+ * DVAs might be invalid or point to vdevs that do not exist.
+ * We skip them.
*/
- for (c = mm->mm_preferred, d = c - 1; d >= 0; d--) {
- if (DVA_GET_VDEV(&dva[d]) == DVA_GET_VDEV(&dva[c]))
- mm->mm_preferred = d;
+ if (!spa_writeable(spa)) {
+ ASSERT3U(zio->io_type, ==, ZIO_TYPE_READ);
+ int j = 0;
+ for (int i = 0; i < c; i++) {
+ if (zfs_dva_valid(spa, &dva[i], zio->io_bp))
+ dva_copy[j++] = dva[i];
+ }
+ if (j == 0) {
+ zio->io_vsd = NULL;
+ zio->io_error = ENXIO;
+ return (NULL);
+ }
+ if (j < c) {
+ dva = dva_copy;
+ c = j;
+ }
}
+ mm = vdev_mirror_map_alloc(c, B_FALSE, B_TRUE);
for (c = 0; c < mm->mm_children; c++) {
mc = &mm->mm_child[c];
mc->mc_vd = vdev_lookup_top(spa, DVA_GET_VDEV(&dva[c]));
mc->mc_offset = DVA_GET_OFFSET(&dva[c]);
+ if (mc->mc_vd == NULL) {
+ kmem_free(mm, vdev_mirror_map_size(
+ mm->mm_children));
+ zio->io_vsd = NULL;
+ zio->io_error = ENXIO;
+ return (NULL);
+ }
}
} else {
- int lowest_pending = INT_MAX;
- int lowest_nr = 1;
-
- c = vd->vdev_children;
-
- mm = kmem_zalloc(offsetof(mirror_map_t, mm_child[c]), KM_PUSHPAGE);
- mm->mm_children = c;
- mm->mm_replacing = (vd->vdev_ops == &vdev_replacing_ops ||
- vd->vdev_ops == &vdev_spare_ops);
- mm->mm_preferred = 0;
- mm->mm_root = B_FALSE;
-
+ /*
+ * If we are resilvering, then we should handle scrub reads
+ * differently; we shouldn't issue them to the resilvering
+ * device because it might not have those blocks.
+ *
+ * We are resilvering iff:
+ * 1) We are a replacing vdev (ie our name is "replacing-1" or
+ * "spare-1" or something like that), and
+ * 2) The pool is currently being resilvered.
+ *
+ * We cannot simply check vd->vdev_resilver_txg, because it's
+ * not set in this path.
+ *
+ * Nor can we just check our vdev_ops; there are cases (such as
+ * when a user types "zpool replace pool odev spare_dev" and
+ * spare_dev is in the spare list, or when a spare device is
+ * automatically used to replace a DEGRADED device) when
+ * resilvering is complete but both the original vdev and the
+ * spare vdev remain in the pool. That behavior is intentional.
+ * It helps implement the policy that a spare should be
+ * automatically removed from the pool after the user replaces
+ * the device that originally failed.
+ *
+ * If a spa load is in progress, then spa_dsl_pool may be
+ * uninitialized. But we shouldn't be resilvering during a spa
+ * load anyway.
+ */
+ boolean_t replacing = (vd->vdev_ops == &vdev_replacing_ops ||
+ vd->vdev_ops == &vdev_spare_ops) &&
+ spa_load_state(vd->vdev_spa) == SPA_LOAD_NONE &&
+ dsl_scan_resilvering(vd->vdev_spa->spa_dsl_pool);
+ mm = vdev_mirror_map_alloc(vd->vdev_children, replacing,
+ B_FALSE);
for (c = 0; c < mm->mm_children; c++) {
mc = &mm->mm_child[c];
mc->mc_vd = vd->vdev_child[c];
mc->mc_offset = zio->io_offset;
- if (mm->mm_replacing)
- continue;
-
- if (!vdev_readable(mc->mc_vd)) {
- mc->mc_error = ENXIO;
- mc->mc_tried = 1;
- mc->mc_skipped = 1;
- mc->mc_pending = INT_MAX;
- continue;
- }
-
- mc->mc_pending = vdev_mirror_pending(mc->mc_vd);
- if (mc->mc_pending < lowest_pending) {
- lowest_pending = mc->mc_pending;
- lowest_nr = 1;
- } else if (mc->mc_pending == lowest_pending) {
- lowest_nr++;
- }
- }
-
- d = gethrtime() / (NSEC_PER_USEC * zfs_vdev_mirror_switch_us);
- d = (d % lowest_nr) + 1;
-
- for (c = 0; c < mm->mm_children; c++) {
- mc = &mm->mm_child[c];
-
- if (mm->mm_child[c].mc_pending == lowest_pending) {
- if (--d == 0) {
- mm->mm_preferred = c;
- break;
- }
- }
+ if (vdev_mirror_rebuilding(mc->mc_vd))
+ mm->mm_rebuilding = mc->mc_rebuilding = B_TRUE;
}
}
- zio->io_vsd = mm;
- zio->io_vsd_ops = &vdev_mirror_vsd_ops;
return (mm);
}
static int
vdev_mirror_open(vdev_t *vd, uint64_t *asize, uint64_t *max_asize,
- uint64_t *ashift)
+ uint64_t *logical_ashift, uint64_t *physical_ashift)
{
int numerrors = 0;
int lasterror = 0;
- int c;
if (vd->vdev_children == 0) {
vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL;
- return (EINVAL);
+ return (SET_ERROR(EINVAL));
}
vdev_open_children(vd);
- for (c = 0; c < vd->vdev_children; c++) {
+ for (int c = 0; c < vd->vdev_children; c++) {
vdev_t *cvd = vd->vdev_child[c];
if (cvd->vdev_open_error) {
*asize = MIN(*asize - 1, cvd->vdev_asize - 1) + 1;
*max_asize = MIN(*max_asize - 1, cvd->vdev_max_asize - 1) + 1;
- *ashift = MAX(*ashift, cvd->vdev_ashift);
+ *logical_ashift = MAX(*logical_ashift, cvd->vdev_ashift);
+ }
+ for (int c = 0; c < vd->vdev_children; c++) {
+ vdev_t *cvd = vd->vdev_child[c];
+
+ if (cvd->vdev_open_error)
+ continue;
+ *physical_ashift = vdev_best_ashift(*logical_ashift,
+ *physical_ashift, cvd->vdev_physical_ashift);
}
if (numerrors == vd->vdev_children) {
- vd->vdev_stat.vs_aux = VDEV_AUX_NO_REPLICAS;
+ if (vdev_children_are_offline(vd))
+ vd->vdev_stat.vs_aux = VDEV_AUX_CHILDREN_OFFLINE;
+ else
+ vd->vdev_stat.vs_aux = VDEV_AUX_NO_REPLICAS;
return (lasterror);
}
static void
vdev_mirror_close(vdev_t *vd)
{
- int c;
-
- for (c = 0; c < vd->vdev_children; c++)
+ for (int c = 0; c < vd->vdev_children; c++)
vdev_close(vd->vdev_child[c]);
}
mc->mc_skipped = 0;
}
-static void
-vdev_mirror_scrub_done(zio_t *zio)
+/*
+ * Check the other, lower-index DVAs to see if they're on the same
+ * vdev as the child we picked. If they are, use them since they
+ * are likely to have been allocated from the primary metaslab in
+ * use at the time, and hence are more likely to have locality with
+ * single-copy data.
+ */
+static int
+vdev_mirror_dva_select(zio_t *zio, int p)
{
- mirror_child_t *mc = zio->io_private;
+ dva_t *dva = zio->io_bp->blk_dva;
+ mirror_map_t *mm = zio->io_vsd;
+ int preferred;
+ int c;
- if (zio->io_error == 0) {
- zio_t *pio;
+ preferred = mm->mm_preferred[p];
+ for (p--; p >= 0; p--) {
+ c = mm->mm_preferred[p];
+ if (DVA_GET_VDEV(&dva[c]) == DVA_GET_VDEV(&dva[preferred]))
+ preferred = c;
+ }
+ return (preferred);
+}
- mutex_enter(&zio->io_lock);
- while ((pio = zio_walk_parents(zio)) != NULL) {
- mutex_enter(&pio->io_lock);
- ASSERT3U(zio->io_size, >=, pio->io_size);
- bcopy(zio->io_data, pio->io_data, pio->io_size);
- mutex_exit(&pio->io_lock);
- }
- mutex_exit(&zio->io_lock);
+static int
+vdev_mirror_preferred_child_randomize(zio_t *zio)
+{
+ mirror_map_t *mm = zio->io_vsd;
+ int p;
+
+ if (mm->mm_root) {
+ p = random_in_range(mm->mm_preferred_cnt);
+ return (vdev_mirror_dva_select(zio, p));
}
- zio_buf_free(zio->io_data, zio->io_size);
+ /*
+ * To ensure we don't always favour the first matching vdev,
+ * which could lead to wear leveling issues on SSD's, we
+ * use the I/O offset as a pseudo random seed into the vdevs
+ * which have the lowest load.
+ */
+ p = (zio->io_offset >> vdev_mirror_shift) % mm->mm_preferred_cnt;
+ return (mm->mm_preferred[p]);
+}
- mc->mc_error = zio->io_error;
- mc->mc_tried = 1;
- mc->mc_skipped = 0;
+static boolean_t
+vdev_mirror_child_readable(mirror_child_t *mc)
+{
+ vdev_t *vd = mc->mc_vd;
+
+ if (vd->vdev_top != NULL && vd->vdev_top->vdev_ops == &vdev_draid_ops)
+ return (vdev_draid_readable(vd, mc->mc_offset));
+ else
+ return (vdev_readable(vd));
+}
+
+static boolean_t
+vdev_mirror_child_missing(mirror_child_t *mc, uint64_t txg, uint64_t size)
+{
+ vdev_t *vd = mc->mc_vd;
+
+ if (vd->vdev_top != NULL && vd->vdev_top->vdev_ops == &vdev_draid_ops)
+ return (vdev_draid_missing(vd, mc->mc_offset, txg, size));
+ else
+ return (vdev_dtl_contains(vd, DTL_MISSING, txg, size));
}
/*
- * Try to find a child whose DTL doesn't contain the block we want to read.
- * If we can't, try the read on any vdev we haven't already tried.
+ * Try to find a vdev whose DTL doesn't contain the block we want to read
+ * preferring vdevs based on determined load. If we can't, try the read on
+ * any vdev we haven't already tried.
+ *
+ * Distributed spares are an exception to the above load rule. They are
+ * always preferred in order to detect gaps in the distributed spare which
+ * are created when another disk in the dRAID fails. In order to restore
+ * redundancy those gaps must be read to trigger the required repair IO.
*/
static int
vdev_mirror_child_select(zio_t *zio)
{
mirror_map_t *mm = zio->io_vsd;
- mirror_child_t *mc;
uint64_t txg = zio->io_txg;
- int i, c;
+ int c, lowest_load;
- ASSERT(zio->io_bp == NULL || BP_PHYSICAL_BIRTH(zio->io_bp) == txg);
+ ASSERT(zio->io_bp == NULL || BP_GET_BIRTH(zio->io_bp) == txg);
+
+ lowest_load = INT_MAX;
+ mm->mm_preferred_cnt = 0;
+ for (c = 0; c < mm->mm_children; c++) {
+ mirror_child_t *mc;
- /*
- * Try to find a child whose DTL doesn't contain the block to read.
- * If a child is known to be completely inaccessible (indicated by
- * vdev_readable() returning B_FALSE), don't even try.
- */
- for (i = 0, c = mm->mm_preferred; i < mm->mm_children; i++, c++) {
- if (c >= mm->mm_children)
- c = 0;
mc = &mm->mm_child[c];
if (mc->mc_tried || mc->mc_skipped)
continue;
- if (!vdev_readable(mc->mc_vd)) {
- mc->mc_error = ENXIO;
+
+ if (mc->mc_vd == NULL ||
+ !vdev_mirror_child_readable(mc)) {
+ mc->mc_error = SET_ERROR(ENXIO);
mc->mc_tried = 1; /* don't even try */
mc->mc_skipped = 1;
continue;
}
- if (!vdev_dtl_contains(mc->mc_vd, DTL_MISSING, txg, 1))
- return (c);
- mc->mc_error = ESTALE;
- mc->mc_skipped = 1;
- mc->mc_speculative = 1;
+
+ if (vdev_mirror_child_missing(mc, txg, 1)) {
+ mc->mc_error = SET_ERROR(ESTALE);
+ mc->mc_skipped = 1;
+ mc->mc_speculative = 1;
+ continue;
+ }
+
+ if (mc->mc_vd->vdev_ops == &vdev_draid_spare_ops) {
+ mm->mm_preferred[0] = c;
+ mm->mm_preferred_cnt = 1;
+ break;
+ }
+
+ mc->mc_load = vdev_mirror_load(mm, mc->mc_vd, mc->mc_offset);
+ if (mc->mc_load > lowest_load)
+ continue;
+
+ if (mc->mc_load < lowest_load) {
+ lowest_load = mc->mc_load;
+ mm->mm_preferred_cnt = 0;
+ }
+ mm->mm_preferred[mm->mm_preferred_cnt] = c;
+ mm->mm_preferred_cnt++;
+ }
+
+ if (mm->mm_preferred_cnt == 1) {
+ MIRROR_BUMP(vdev_mirror_stat_preferred_found);
+ return (mm->mm_preferred[0]);
+ }
+
+ if (mm->mm_preferred_cnt > 1) {
+ MIRROR_BUMP(vdev_mirror_stat_preferred_not_found);
+ return (vdev_mirror_preferred_child_randomize(zio));
}
/*
* Every device is either missing or has this txg in its DTL.
* Look for any child we haven't already tried before giving up.
*/
- for (c = 0; c < mm->mm_children; c++)
+ for (c = 0; c < mm->mm_children; c++) {
if (!mm->mm_child[c].mc_tried)
return (c);
+ }
/*
* Every child failed. There's no place left to look.
return (-1);
}
-static int
+static void
vdev_mirror_io_start(zio_t *zio)
{
mirror_map_t *mm;
mirror_child_t *mc;
int c, children;
- mm = vdev_mirror_map_alloc(zio);
+ mm = vdev_mirror_map_init(zio);
+ zio->io_vsd = mm;
+ zio->io_vsd_ops = &vdev_mirror_vsd_ops;
+
+ if (mm == NULL) {
+ ASSERT(!spa_trust_config(zio->io_spa));
+ ASSERT(zio->io_type == ZIO_TYPE_READ);
+ zio_execute(zio);
+ return;
+ }
if (zio->io_type == ZIO_TYPE_READ) {
- if ((zio->io_flags & ZIO_FLAG_SCRUB) && !mm->mm_replacing) {
+ if ((zio->io_flags & ZIO_FLAG_SCRUB) && !mm->mm_resilvering) {
/*
- * For scrubbing reads we need to allocate a read
- * buffer for each child and issue reads to all
- * children. If any child succeeds, it will copy its
- * data into zio->io_data in vdev_mirror_scrub_done.
+ * For scrubbing reads we need to issue reads to all
+ * children. One child can reuse parent buffer, but
+ * for others we have to allocate separate ones to
+ * verify checksums if io_bp is non-NULL, or compare
+ * them in vdev_mirror_io_done() otherwise.
*/
+ boolean_t first = B_TRUE;
for (c = 0; c < mm->mm_children; c++) {
mc = &mm->mm_child[c];
+
+ /* Don't issue ZIOs to offline children */
+ if (!vdev_mirror_child_readable(mc)) {
+ mc->mc_error = SET_ERROR(ENXIO);
+ mc->mc_tried = 1;
+ mc->mc_skipped = 1;
+ continue;
+ }
+
+ mc->mc_abd = first ? zio->io_abd :
+ abd_alloc_sametype(zio->io_abd,
+ zio->io_size);
zio_nowait(zio_vdev_child_io(zio, zio->io_bp,
- mc->mc_vd, mc->mc_offset,
- zio_buf_alloc(zio->io_size), zio->io_size,
- zio->io_type, zio->io_priority, 0,
- vdev_mirror_scrub_done, mc));
+ mc->mc_vd, mc->mc_offset, mc->mc_abd,
+ zio->io_size, zio->io_type,
+ zio->io_priority, 0,
+ vdev_mirror_child_done, mc));
+ first = B_FALSE;
}
- return (ZIO_PIPELINE_CONTINUE);
+ zio_execute(zio);
+ return;
}
/*
* For normal reads just pick one child.
while (children--) {
mc = &mm->mm_child[c];
+ c++;
+
+ /*
+ * When sequentially resilvering only issue write repair
+ * IOs to the vdev which is being rebuilt since performance
+ * is limited by the slowest child. This is an issue for
+ * faster replacement devices such as distributed spares.
+ */
+ if ((zio->io_priority == ZIO_PRIORITY_REBUILD) &&
+ (zio->io_flags & ZIO_FLAG_IO_REPAIR) &&
+ !(zio->io_flags & ZIO_FLAG_SCRUB) &&
+ mm->mm_rebuilding && !mc->mc_rebuilding) {
+ continue;
+ }
+
zio_nowait(zio_vdev_child_io(zio, zio->io_bp,
- mc->mc_vd, mc->mc_offset, zio->io_data, zio->io_size,
+ mc->mc_vd, mc->mc_offset, zio->io_abd, zio->io_size,
zio->io_type, zio->io_priority, 0,
vdev_mirror_child_done, mc));
- c++;
}
- return (ZIO_PIPELINE_CONTINUE);
+ zio_execute(zio);
}
static int
vdev_mirror_worst_error(mirror_map_t *mm)
{
- int c, error[2] = { 0, 0 };
+ int error[2] = { 0, 0 };
- for (c = 0; c < mm->mm_children; c++) {
+ for (int c = 0; c < mm->mm_children; c++) {
mirror_child_t *mc = &mm->mm_child[c];
int s = mc->mc_speculative;
error[s] = zio_worst_error(error[s], mc->mc_error);
int c;
int good_copies = 0;
int unexpected_errors = 0;
+ int last_good_copy = -1;
+
+ if (mm == NULL)
+ return;
for (c = 0; c < mm->mm_children; c++) {
mc = &mm->mm_child[c];
if (!mc->mc_skipped)
unexpected_errors++;
} else if (mc->mc_tried) {
+ last_good_copy = c;
good_copies++;
}
}
* no non-degraded top-level vdevs left, and not update DTLs
* if we intend to reallocate.
*/
- /* XXPOLICY */
if (good_copies != mm->mm_children) {
/*
* Always require at least one good copy.
/*
* If we don't have a good copy yet, keep trying other children.
*/
- /* XXPOLICY */
if (good_copies == 0 && (c = vdev_mirror_child_select(zio)) != -1) {
ASSERT(c >= 0 && c < mm->mm_children);
mc = &mm->mm_child[c];
zio_vdev_io_redone(zio);
zio_nowait(zio_vdev_child_io(zio, zio->io_bp,
- mc->mc_vd, mc->mc_offset, zio->io_data, zio->io_size,
+ mc->mc_vd, mc->mc_offset, zio->io_abd, zio->io_size,
ZIO_TYPE_READ, zio->io_priority, 0,
vdev_mirror_child_done, mc));
return;
}
- /* XXPOLICY */
+ if (zio->io_flags & ZIO_FLAG_SCRUB && !mm->mm_resilvering) {
+ abd_t *best_abd = NULL;
+ if (last_good_copy >= 0)
+ best_abd = mm->mm_child[last_good_copy].mc_abd;
+
+ /*
+ * If we're scrubbing but don't have a BP available (because
+ * this vdev is under a raidz or draid vdev) then the best we
+ * can do is compare all of the copies read. If they're not
+ * identical then return a checksum error and the most likely
+ * correct data. The raidz code will issue a repair I/O if
+ * possible.
+ */
+ if (zio->io_bp == NULL) {
+ ASSERT(zio->io_vd->vdev_ops == &vdev_replacing_ops ||
+ zio->io_vd->vdev_ops == &vdev_spare_ops);
+
+ abd_t *pref_abd = NULL;
+ for (c = 0; c < last_good_copy; c++) {
+ mc = &mm->mm_child[c];
+ if (mc->mc_error || !mc->mc_tried)
+ continue;
+
+ if (abd_cmp(mc->mc_abd, best_abd) != 0)
+ zio->io_error = SET_ERROR(ECKSUM);
+
+ /*
+ * The distributed spare is always prefered
+ * by vdev_mirror_child_select() so it's
+ * considered to be the best candidate.
+ */
+ if (pref_abd == NULL &&
+ mc->mc_vd->vdev_ops ==
+ &vdev_draid_spare_ops)
+ pref_abd = mc->mc_abd;
+
+ /*
+ * In the absence of a preferred copy, use
+ * the parent pointer to avoid a memory copy.
+ */
+ if (mc->mc_abd == zio->io_abd)
+ best_abd = mc->mc_abd;
+ }
+ if (pref_abd)
+ best_abd = pref_abd;
+ } else {
+
+ /*
+ * If we have a BP available, then checksums are
+ * already verified and we just need a buffer
+ * with valid data, preferring parent one to
+ * avoid a memory copy.
+ */
+ for (c = 0; c < last_good_copy; c++) {
+ mc = &mm->mm_child[c];
+ if (mc->mc_error || !mc->mc_tried)
+ continue;
+ if (mc->mc_abd == zio->io_abd) {
+ best_abd = mc->mc_abd;
+ break;
+ }
+ }
+ }
+
+ if (best_abd && best_abd != zio->io_abd)
+ abd_copy(zio->io_abd, best_abd, zio->io_size);
+ for (c = 0; c < mm->mm_children; c++) {
+ mc = &mm->mm_child[c];
+ if (mc->mc_abd != zio->io_abd)
+ abd_free(mc->mc_abd);
+ mc->mc_abd = NULL;
+ }
+ }
+
if (good_copies == 0) {
zio->io_error = vdev_mirror_worst_error(mm);
ASSERT(zio->io_error != 0);
if (good_copies && spa_writeable(zio->io_spa) &&
(unexpected_errors ||
(zio->io_flags & ZIO_FLAG_RESILVER) ||
- ((zio->io_flags & ZIO_FLAG_SCRUB) && mm->mm_replacing))) {
+ ((zio->io_flags & ZIO_FLAG_SCRUB) && mm->mm_resilvering))) {
/*
* Use the good data we have in hand to repair damaged children.
*/
mc = &mm->mm_child[c];
if (mc->mc_error == 0) {
+ vdev_ops_t *ops = mc->mc_vd->vdev_ops;
+
if (mc->mc_tried)
continue;
+ /*
+ * We didn't try this child. We need to
+ * repair it if:
+ * 1. it's a scrub (in which case we have
+ * tried everything that was healthy)
+ * - or -
+ * 2. it's an indirect or distributed spare
+ * vdev (in which case it could point to any
+ * other vdev, which might have a bad DTL)
+ * - or -
+ * 3. the DTL indicates that this data is
+ * missing from this vdev
+ */
if (!(zio->io_flags & ZIO_FLAG_SCRUB) &&
+ ops != &vdev_indirect_ops &&
+ ops != &vdev_draid_spare_ops &&
!vdev_dtl_contains(mc->mc_vd, DTL_PARTIAL,
zio->io_txg, 1))
continue;
- mc->mc_error = ESTALE;
+ mc->mc_error = SET_ERROR(ESTALE);
}
zio_nowait(zio_vdev_child_io(zio, zio->io_bp,
mc->mc_vd, mc->mc_offset,
- zio->io_data, zio->io_size,
- ZIO_TYPE_WRITE, zio->io_priority,
+ zio->io_abd, zio->io_size, ZIO_TYPE_WRITE,
+ zio->io_priority == ZIO_PRIORITY_REBUILD ?
+ ZIO_PRIORITY_REBUILD : ZIO_PRIORITY_ASYNC_WRITE,
ZIO_FLAG_IO_REPAIR | (unexpected_errors ?
ZIO_FLAG_SELF_HEAL : 0), NULL, NULL));
}
static void
vdev_mirror_state_change(vdev_t *vd, int faulted, int degraded)
{
- if (faulted == vd->vdev_children)
- vdev_set_state(vd, B_FALSE, VDEV_STATE_CANT_OPEN,
- VDEV_AUX_NO_REPLICAS);
- else if (degraded + faulted != 0)
+ if (faulted == vd->vdev_children) {
+ if (vdev_children_are_offline(vd)) {
+ vdev_set_state(vd, B_FALSE, VDEV_STATE_OFFLINE,
+ VDEV_AUX_CHILDREN_OFFLINE);
+ } else {
+ vdev_set_state(vd, B_FALSE, VDEV_STATE_CANT_OPEN,
+ VDEV_AUX_NO_REPLICAS);
+ }
+ } else if (degraded + faulted != 0) {
vdev_set_state(vd, B_FALSE, VDEV_STATE_DEGRADED, VDEV_AUX_NONE);
- else
+ } else {
vdev_set_state(vd, B_FALSE, VDEV_STATE_HEALTHY, VDEV_AUX_NONE);
+ }
+}
+
+/*
+ * Return the maximum asize for a rebuild zio in the provided range.
+ */
+static uint64_t
+vdev_mirror_rebuild_asize(vdev_t *vd, uint64_t start, uint64_t asize,
+ uint64_t max_segment)
+{
+ (void) start;
+
+ uint64_t psize = MIN(P2ROUNDUP(max_segment, 1 << vd->vdev_ashift),
+ SPA_MAXBLOCKSIZE);
+
+ return (MIN(asize, vdev_psize_to_asize(vd, psize)));
}
vdev_ops_t vdev_mirror_ops = {
- vdev_mirror_open,
- vdev_mirror_close,
- vdev_default_asize,
- vdev_mirror_io_start,
- vdev_mirror_io_done,
- vdev_mirror_state_change,
- NULL,
- NULL,
- VDEV_TYPE_MIRROR, /* name of this vdev type */
- B_FALSE /* not a leaf vdev */
+ .vdev_op_init = NULL,
+ .vdev_op_fini = NULL,
+ .vdev_op_open = vdev_mirror_open,
+ .vdev_op_close = vdev_mirror_close,
+ .vdev_op_asize = vdev_default_asize,
+ .vdev_op_min_asize = vdev_default_min_asize,
+ .vdev_op_min_alloc = NULL,
+ .vdev_op_io_start = vdev_mirror_io_start,
+ .vdev_op_io_done = vdev_mirror_io_done,
+ .vdev_op_state_change = vdev_mirror_state_change,
+ .vdev_op_need_resilver = vdev_default_need_resilver,
+ .vdev_op_hold = NULL,
+ .vdev_op_rele = NULL,
+ .vdev_op_remap = NULL,
+ .vdev_op_xlate = vdev_default_xlate,
+ .vdev_op_rebuild_asize = vdev_mirror_rebuild_asize,
+ .vdev_op_metaslab_init = NULL,
+ .vdev_op_config_generate = NULL,
+ .vdev_op_nparity = NULL,
+ .vdev_op_ndisks = NULL,
+ .vdev_op_type = VDEV_TYPE_MIRROR, /* name of this vdev type */
+ .vdev_op_leaf = B_FALSE /* not a leaf vdev */
};
vdev_ops_t vdev_replacing_ops = {
- vdev_mirror_open,
- vdev_mirror_close,
- vdev_default_asize,
- vdev_mirror_io_start,
- vdev_mirror_io_done,
- vdev_mirror_state_change,
- NULL,
- NULL,
- VDEV_TYPE_REPLACING, /* name of this vdev type */
- B_FALSE /* not a leaf vdev */
+ .vdev_op_init = NULL,
+ .vdev_op_fini = NULL,
+ .vdev_op_open = vdev_mirror_open,
+ .vdev_op_close = vdev_mirror_close,
+ .vdev_op_asize = vdev_default_asize,
+ .vdev_op_min_asize = vdev_default_min_asize,
+ .vdev_op_min_alloc = NULL,
+ .vdev_op_io_start = vdev_mirror_io_start,
+ .vdev_op_io_done = vdev_mirror_io_done,
+ .vdev_op_state_change = vdev_mirror_state_change,
+ .vdev_op_need_resilver = vdev_default_need_resilver,
+ .vdev_op_hold = NULL,
+ .vdev_op_rele = NULL,
+ .vdev_op_remap = NULL,
+ .vdev_op_xlate = vdev_default_xlate,
+ .vdev_op_rebuild_asize = vdev_mirror_rebuild_asize,
+ .vdev_op_metaslab_init = NULL,
+ .vdev_op_config_generate = NULL,
+ .vdev_op_nparity = NULL,
+ .vdev_op_ndisks = NULL,
+ .vdev_op_type = VDEV_TYPE_REPLACING, /* name of this vdev type */
+ .vdev_op_leaf = B_FALSE /* not a leaf vdev */
};
vdev_ops_t vdev_spare_ops = {
- vdev_mirror_open,
- vdev_mirror_close,
- vdev_default_asize,
- vdev_mirror_io_start,
- vdev_mirror_io_done,
- vdev_mirror_state_change,
- NULL,
- NULL,
- VDEV_TYPE_SPARE, /* name of this vdev type */
- B_FALSE /* not a leaf vdev */
+ .vdev_op_init = NULL,
+ .vdev_op_fini = NULL,
+ .vdev_op_open = vdev_mirror_open,
+ .vdev_op_close = vdev_mirror_close,
+ .vdev_op_asize = vdev_default_asize,
+ .vdev_op_min_asize = vdev_default_min_asize,
+ .vdev_op_min_alloc = NULL,
+ .vdev_op_io_start = vdev_mirror_io_start,
+ .vdev_op_io_done = vdev_mirror_io_done,
+ .vdev_op_state_change = vdev_mirror_state_change,
+ .vdev_op_need_resilver = vdev_default_need_resilver,
+ .vdev_op_hold = NULL,
+ .vdev_op_rele = NULL,
+ .vdev_op_remap = NULL,
+ .vdev_op_xlate = vdev_default_xlate,
+ .vdev_op_rebuild_asize = vdev_mirror_rebuild_asize,
+ .vdev_op_metaslab_init = NULL,
+ .vdev_op_config_generate = NULL,
+ .vdev_op_nparity = NULL,
+ .vdev_op_ndisks = NULL,
+ .vdev_op_type = VDEV_TYPE_SPARE, /* name of this vdev type */
+ .vdev_op_leaf = B_FALSE /* not a leaf vdev */
};
-#if defined(_KERNEL) && defined(HAVE_SPL)
-module_param(zfs_vdev_mirror_switch_us, int, 0644);
-MODULE_PARM_DESC(zfs_vdev_mirror_switch_us, "Switch mirrors every N usecs");
-#endif
+ZFS_MODULE_PARAM(zfs_vdev_mirror, zfs_vdev_mirror_, rotating_inc, INT, ZMOD_RW,
+ "Rotating media load increment for non-seeking I/Os");
+
+ZFS_MODULE_PARAM(zfs_vdev_mirror, zfs_vdev_mirror_, rotating_seek_inc, INT,
+ ZMOD_RW, "Rotating media load increment for seeking I/Os");
+
+/* BEGIN CSTYLED */
+ZFS_MODULE_PARAM(zfs_vdev_mirror, zfs_vdev_mirror_, rotating_seek_offset, INT,
+ ZMOD_RW,
+ "Offset in bytes from the last I/O which triggers "
+ "a reduced rotating media seek increment");
+/* END CSTYLED */
+
+ZFS_MODULE_PARAM(zfs_vdev_mirror, zfs_vdev_mirror_, non_rotating_inc, INT,
+ ZMOD_RW, "Non-rotating media load increment for non-seeking I/Os");
+
+ZFS_MODULE_PARAM(zfs_vdev_mirror, zfs_vdev_mirror_, non_rotating_seek_inc, INT,
+ ZMOD_RW, "Non-rotating media load increment for seeking I/Os");