#define dout_context cct
#define dout_subsys ceph_subsys_bluestore
#undef dout_prefix
-#define dout_prefix *_dout << "ZonedAllocator " << this << " "
+#define dout_prefix *_dout << "ZonedAllocator(" << this << ") " << __func__ << " "
ZonedAllocator::ZonedAllocator(CephContext* cct,
int64_t size,
- int64_t block_size,
- const std::string& name)
- : Allocator(name, size, block_size),
+ int64_t blk_size,
+ int64_t _zone_size,
+ int64_t _first_sequential_zone,
+ std::string_view name)
+ : Allocator(name, size, blk_size),
cct(cct),
- num_free(0),
size(size),
- // To avoid interface changes, we piggyback zone size and the first
- // sequential zone number onto the first 32 bits of 64-bit |block_size|.
- // The last 32 bits of |block_size| is holding the actual block size.
- block_size((block_size & 0x00000000ffffffff)),
- zone_size(((block_size & 0x0000ffff00000000) >> 32) * 1024 * 1024),
- starting_zone_num((block_size & 0xffff000000000000) >> 48),
- num_zones(size / zone_size) {
- ldout(cct, 10) << __func__ << " size 0x" << std::hex << size
- << " zone size 0x" << zone_size << std::dec
- << " number of zones " << num_zones
- << " first sequential zone " << starting_zone_num
+ conventional_size(_first_sequential_zone * _zone_size),
+ sequential_size(size - conventional_size),
+ num_sequential_free(0),
+ block_size(blk_size),
+ zone_size(_zone_size),
+ first_seq_zone_num(_first_sequential_zone),
+ starting_zone_num(first_seq_zone_num),
+ num_zones(size / zone_size)
+{
+ ldout(cct, 10) << " size 0x" << std::hex << size
+ << ", zone size 0x" << zone_size << std::dec
+ << ", number of zones 0x" << num_zones
+ << ", first sequential zone 0x" << starting_zone_num
+ << ", sequential size 0x" << sequential_size
+ << std::dec
<< dendl;
ceph_assert(size % zone_size == 0);
+
+ zone_states.resize(num_zones);
}
-ZonedAllocator::~ZonedAllocator() {}
+ZonedAllocator::~ZonedAllocator()
+{
+}
int64_t ZonedAllocator::allocate(
uint64_t want_size,
uint64_t alloc_unit,
uint64_t max_alloc_size,
int64_t hint,
- PExtentVector *extents) {
+ PExtentVector *extents)
+{
std::lock_guard l(lock);
ceph_assert(want_size % 4096 == 0);
- ldout(cct, 10) << __func__ << " trying to allocate "
- << std::hex << want_size << dendl;
+ ldout(cct, 10) << " trying to allocate 0x"
+ << std::hex << want_size << std::dec << dendl;
+ uint64_t left = num_zones - first_seq_zone_num;
uint64_t zone_num = starting_zone_num;
- for ( ; zone_num < num_zones; ++zone_num) {
- if (fits(want_size, zone_num)) {
- break;
+ for ( ; left > 0; ++zone_num, --left) {
+ if (zone_num == num_zones) {
+ zone_num = first_seq_zone_num;
}
- ldout(cct, 10) << __func__ << " skipping zone " << zone_num
- << " because there is not enough space: "
- << " want_size = " << want_size
- << " available = " << get_remaining_space(zone_num)
- << dendl;
+ if (zone_num == cleaning_zone) {
+ ldout(cct, 10) << " skipping zone 0x" << std::hex << zone_num
+ << " because we are cleaning it" << std::dec << dendl;
+ continue;
+ }
+ if (!fits(want_size, zone_num)) {
+ ldout(cct, 10) << " skipping zone 0x" << std::hex << zone_num
+ << " because there is not enough space: "
+ << " want_size = 0x" << want_size
+ << " available = 0x" << get_remaining_space(zone_num)
+ << std::dec
+ << dendl;
+ continue;
+ }
+ break;
}
- if (zone_num == num_zones) {
- ldout(cct, 10) << __func__ << " failed to allocate" << dendl;
+ if (left == 0) {
+ ldout(cct, 10) << " failed to allocate" << dendl;
return -ENOSPC;
}
uint64_t offset = get_offset(zone_num);
- ldout(cct, 10) << __func__ << " advancing zone " << std::hex
- << zone_num << " write pointer from " << offset
- << " to " << offset + want_size << dendl;
+ ldout(cct, 10) << " moving zone 0x" << std::hex
+ << zone_num << " write pointer from 0x" << offset
+ << " -> 0x" << offset + want_size
+ << std::dec << dendl;
- advance_write_pointer(zone_num, want_size);
+ increment_write_pointer(zone_num, want_size);
+ num_sequential_free -= want_size;
if (get_remaining_space(zone_num) == 0) {
starting_zone_num = zone_num + 1;
}
- ldout(cct, 10) << __func__ << std::hex << " zone " << zone_num
- << " offset is now " << get_write_pointer(zone_num) << dendl;
-
- ldout(cct, 10) << __func__ << " allocated " << std::hex << want_size
- << " bytes at offset " << offset
- << " located at zone " << zone_num
- << " and zone offset " << offset % zone_size << dendl;
+ ldout(cct, 10) << " allocated 0x" << std::hex << offset << "~" << want_size
+ << " from zone 0x" << zone_num
+ << " and zone offset 0x" << (offset % zone_size)
+ << std::dec << dendl;
extents->emplace_back(bluestore_pextent_t(offset, want_size));
return want_size;
}
-void ZonedAllocator::release(const interval_set<uint64_t>& release_set) {
+void ZonedAllocator::release(const interval_set<uint64_t>& release_set)
+{
std::lock_guard l(lock);
+ for (auto p = cbegin(release_set); p != cend(release_set); ++p) {
+ auto offset = p.get_start();
+ auto length = p.get_len();
+ uint64_t zone_num = offset / zone_size;
+ ldout(cct, 10) << " 0x" << std::hex << offset << "~" << length
+ << " from zone 0x" << zone_num << std::dec << dendl;
+ uint64_t num_dead = std::min(zone_size - offset % zone_size, length);
+ for ( ; length; ++zone_num) {
+ increment_num_dead_bytes(zone_num, num_dead);
+ length -= num_dead;
+ num_dead = std::min(zone_size, length);
+ }
+ }
}
-uint64_t ZonedAllocator::get_free() {
- return num_free;
+uint64_t ZonedAllocator::get_free()
+{
+ return num_sequential_free;
}
-void ZonedAllocator::dump() {
+void ZonedAllocator::dump()
+{
std::lock_guard l(lock);
}
void ZonedAllocator::dump(std::function<void(uint64_t offset,
- uint64_t length)> notify) {
+ uint64_t length)> notify)
+{
std::lock_guard l(lock);
}
-// This just increments |num_free|. The actual free space is added by
-// set_zone_states, as it updates the write pointer for each zone.
-void ZonedAllocator::init_add_free(uint64_t offset, uint64_t length) {
- ldout(cct, 40) << __func__ << " " << std::hex
- << offset << "~" << length << dendl;
-
- num_free += length;
-}
-
-void ZonedAllocator::init_rm_free(uint64_t offset, uint64_t length) {
+void ZonedAllocator::init_from_zone_pointers(
+ std::vector<zone_state_t> &&_zone_states)
+{
+ // this is called once, based on the device's zone pointers
std::lock_guard l(lock);
- ldout(cct, 40) << __func__ << " 0x" << std::hex
- << offset << "~" << length << dendl;
-
- num_free -= length;
- ceph_assert(num_free >= 0);
-
- uint64_t zone_num = offset / zone_size;
- uint64_t write_pointer = offset % zone_size;
- uint64_t remaining_space = get_remaining_space(zone_num);
-
- ceph_assert(get_write_pointer(zone_num) == write_pointer);
- ceph_assert(remaining_space <= length);
- advance_write_pointer(zone_num, remaining_space);
-
- ldout(cct, 40) << __func__ << " set zone 0x" << std::hex
- << zone_num << " write pointer to 0x" << zone_size << dendl;
-
- length -= remaining_space;
- ceph_assert(length % zone_size == 0);
-
- for ( ; length; length -= zone_size) {
- advance_write_pointer(++zone_num, zone_size);
- ldout(cct, 40) << __func__ << " set zone 0x" << std::hex
- << zone_num << " write pointer to 0x" << zone_size << dendl;
+ ldout(cct, 10) << dendl;
+ zone_states = std::move(_zone_states);
+ num_sequential_free = 0;
+ for (size_t i = first_seq_zone_num; i < num_zones; ++i) {
+ num_sequential_free += zone_size - (zone_states[i].write_pointer % zone_size);
}
+ ldout(cct, 10) << "free 0x" << std::hex << num_sequential_free
+ << " / 0x" << sequential_size << std::dec
+ << dendl;
}
-bool ZonedAllocator::zoned_get_zones_to_clean(std::deque<uint64_t> *zones_to_clean) {
- // TODO: make 0.25 tunable
- if (static_cast<double>(num_free) / size > 0.25) {
- return false;
+int64_t ZonedAllocator::pick_zone_to_clean(float min_score, uint64_t min_saved)
+{
+ std::lock_guard l(lock);
+ int32_t best = -1;
+ float best_score = 0.0;
+ for (size_t i = first_seq_zone_num; i < num_zones; ++i) {
+ // value (score) = benefit / cost
+ // benefit = how much net free space we'll get (dead bytes)
+ // cost = how many bytes we'll have to rewrite (live bytes)
+ // avoid divide by zero on a zone with no live bytes
+ float score =
+ (float)zone_states[i].num_dead_bytes /
+ (float)(zone_states[i].get_num_live_bytes() + 1);
+ if (score > 0) {
+ ldout(cct, 20) << " zone 0x" << std::hex << i
+ << " dead 0x" << zone_states[i].num_dead_bytes
+ << " score " << score
+ << dendl;
+ }
+ if (zone_states[i].num_dead_bytes < min_saved) {
+ continue;
+ }
+ if (best < 0 || score > best_score) {
+ best = i;
+ best_score = score;
+ }
}
- {
- std::lock_guard l(lock);
- // TODO: populate |zones_to_clean| with the numbers of zones that should be
- // cleaned.
+ if (best_score >= min_score) {
+ ldout(cct, 10) << " zone 0x" << std::hex << best << " with score " << best_score
+ << ": 0x" << zone_states[best].num_dead_bytes
+ << " dead and 0x"
+ << zone_states[best].write_pointer - zone_states[best].num_dead_bytes
+ << " live bytes" << std::dec << dendl;
+ } else if (best > 0) {
+ ldout(cct, 10) << " zone 0x" << std::hex << best << " with score " << best_score
+ << ": 0x" << zone_states[best].num_dead_bytes
+ << " dead and 0x"
+ << zone_states[best].write_pointer - zone_states[best].num_dead_bytes
+ << " live bytes" << std::dec
+ << " but below min_score " << min_score
+ << dendl;
+ best = -1;
+ } else {
+ ldout(cct, 10) << " no zones found that are good cleaning candidates" << dendl;
}
- return true;
+ return best;
+}
+
+void ZonedAllocator::reset_zone(uint32_t zone)
+{
+ num_sequential_free += zone_states[zone].write_pointer;
+ zone_states[zone].reset();
}
-void ZonedAllocator::zoned_set_zone_states(std::vector<zone_state_t> &&_zone_states) {
+bool ZonedAllocator::low_on_space(void)
+{
std::lock_guard l(lock);
- ldout(cct, 10) << __func__ << dendl;
- zone_states = std::move(_zone_states);
+ double free_ratio = static_cast<double>(num_sequential_free) / sequential_size;
+
+ ldout(cct, 10) << " free 0x" << std::hex << num_sequential_free
+ << "/ 0x" << sequential_size << std::dec
+ << ", free ratio is " << free_ratio << dendl;
+ ceph_assert(num_sequential_free <= (int64_t)sequential_size);
+
+ // TODO: make 0.25 tunable
+ return free_ratio <= 0.25;
}
-void ZonedAllocator::shutdown() {
- ldout(cct, 1) << __func__ << dendl;
+void ZonedAllocator::shutdown()
+{
+ ldout(cct, 1) << dendl;
}