From f16e78cb50ce676dea823ed7362db4c5b5eaa70b Mon Sep 17 00:00:00 2001 From: Alexander Motin Date: Tue, 23 Nov 2021 21:14:31 -0500 Subject: [PATCH] Improve log spacemap load time after unclean export. Previous flushing algorithm limited only total number of log blocks to the minimum of 256K and 4x number of metaslabs in the pool. As result, system with 1500 disks with 200 metaslabs each, touching several new metaslabs each TXG could grow spacemap log to huge size without much benefits. We've observed one of such systems importing pool after unclean export for about 45 minutes. This patch improves the situation from four sides: - By limiting maximum period for each metaslab to be flushed to 1000 TXGs, that effectively limits maximum number of per-TXG spacemap logs to load after unclean export to the same number. - By making flushing more smooth via accounting number of metaslabs that were touched after the last flush and actually need another flush, not just ms_unflushed_txg bump. - By applying zfs_unflushed_log_block_pct to the number of metaslabs that were touched after the last flush, not all metaslabs in the pool. - By aggressively prefetching per-TXG spacemap logs up to 16 TXGs in advance, making log spacemap load process for wide HDD pool CPU-bound, accelerating it by many times. As further optimization we could skip bumping ms_unflushed_txg for metaslabs not touched since the last flush, but that would be an incompatible change, requiring new pool feature. Signed-off-by: Alexander Motin Sponsored-By: iXsystems, Inc. --- include/sys/dmu.h | 2 + include/sys/metaslab.h | 3 + include/sys/metaslab_impl.h | 1 + include/sys/spa_log_spacemap.h | 9 +- man/man4/zfs.4 | 7 +- module/zfs/metaslab.c | 132 +++++++++++-------- module/zfs/spa.c | 2 +- module/zfs/spa_log_spacemap.c | 229 ++++++++++++++++++++++----------- module/zfs/vdev.c | 7 - module/zfs/vdev_removal.c | 2 - 10 files changed, 252 insertions(+), 142 deletions(-) diff --git a/include/sys/dmu.h b/include/sys/dmu.h index 942ab9b10835..311a2986b075 100644 --- a/include/sys/dmu.h +++ b/include/sys/dmu.h @@ -1069,6 +1069,8 @@ int dmu_diff(const char *tosnap_name, const char *fromsnap_name, #define ZFS_CRC64_POLY 0xC96C5795D7870F42ULL /* ECMA-182, reflected form */ extern uint64_t zfs_crc64_table[256]; +extern int dmu_prefetch_max; + #ifdef __cplusplus } #endif diff --git a/include/sys/metaslab.h b/include/sys/metaslab.h index ecff65f13de5..2b4f7243bbbd 100644 --- a/include/sys/metaslab.h +++ b/include/sys/metaslab.h @@ -49,11 +49,14 @@ int metaslab_init(metaslab_group_t *, uint64_t, uint64_t, uint64_t, metaslab_t **); void metaslab_fini(metaslab_t *); +void metaslab_set_unflushed_dirty(metaslab_t *, boolean_t); void metaslab_set_unflushed_txg(metaslab_t *, uint64_t, dmu_tx_t *); void metaslab_set_estimated_condensed_size(metaslab_t *, uint64_t, dmu_tx_t *); +boolean_t metaslab_unflushed_dirty(metaslab_t *); uint64_t metaslab_unflushed_txg(metaslab_t *); uint64_t metaslab_estimated_condensed_size(metaslab_t *); int metaslab_sort_by_flushed(const void *, const void *); +void metaslab_unflushed_bump(metaslab_t *, dmu_tx_t *, boolean_t); uint64_t metaslab_unflushed_changes_memused(metaslab_t *); int metaslab_load(metaslab_t *); diff --git a/include/sys/metaslab_impl.h b/include/sys/metaslab_impl.h index adf4c03a20db..904249cf4ad5 100644 --- a/include/sys/metaslab_impl.h +++ b/include/sys/metaslab_impl.h @@ -553,6 +553,7 @@ struct metaslab { * log space maps. */ uint64_t ms_unflushed_txg; + boolean_t ms_unflushed_dirty; /* updated every time we are done syncing the metaslab's space map */ uint64_t ms_synced_length; diff --git a/include/sys/spa_log_spacemap.h b/include/sys/spa_log_spacemap.h index b2ed77fac3e4..72229df6cd16 100644 --- a/include/sys/spa_log_spacemap.h +++ b/include/sys/spa_log_spacemap.h @@ -30,7 +30,10 @@ typedef struct log_summary_entry { uint64_t lse_start; /* start TXG */ + uint64_t lse_end; /* last TXG */ + uint64_t lse_txgcount; /* # of TXGs */ uint64_t lse_mscount; /* # of metaslabs needed to be flushed */ + uint64_t lse_msdcount; /* # of dirty metaslabs needed to be flushed */ uint64_t lse_blkcount; /* blocks held by this entry */ list_node_t lse_node; } log_summary_entry_t; @@ -50,6 +53,7 @@ typedef struct spa_log_sm { uint64_t sls_nblocks; /* number of blocks in this log */ uint64_t sls_mscount; /* # of metaslabs flushed in the log's txg */ avl_node_t sls_node; /* node in spa_sm_logs_by_txg */ + space_map_t *sls_sm; /* space map pointer, if open */ } spa_log_sm_t; int spa_ld_log_spacemaps(spa_t *); @@ -68,8 +72,9 @@ uint64_t spa_log_sm_memused(spa_t *); void spa_log_sm_decrement_mscount(spa_t *, uint64_t); void spa_log_sm_increment_current_mscount(spa_t *); -void spa_log_summary_add_flushed_metaslab(spa_t *); -void spa_log_summary_decrement_mscount(spa_t *, uint64_t); +void spa_log_summary_add_flushed_metaslab(spa_t *, boolean_t); +void spa_log_summary_dirty_flushed_metaslab(spa_t *, uint64_t); +void spa_log_summary_decrement_mscount(spa_t *, uint64_t, boolean_t); void spa_log_summary_decrement_blkcount(spa_t *, uint64_t); boolean_t spa_flush_all_logs_requested(spa_t *); diff --git a/man/man4/zfs.4 b/man/man4/zfs.4 index 9c21688705b8..36705d1fc9aa 100644 --- a/man/man4/zfs.4 +++ b/man/man4/zfs.4 @@ -1000,7 +1000,12 @@ Thus we always allow at least this many log blocks. .It Sy zfs_unflushed_log_block_pct Ns = Ns Sy 400 Ns % Pq ulong Tunable used to determine the number of blocks that can be used for the spacemap log, expressed as a percentage of the total number of -metaslabs in the pool. +unflushed metaslabs in the pool. +. +.It Sy zfs_unflushed_log_txg_max Ns = Ns Sy 1000 Pq ulong +Tunable limiting maximum time in TXGs any metaslab may remain unflushed. +It effectively limits maximum number of unflushed per-TXG spacemap logs +that need to be read after unclean pool export. . .It Sy zfs_unlink_suspend_progress Ns = Ns Sy 0 Ns | Ns 1 Pq uint When enabled, files will not be asynchronously removed from the list of pending diff --git a/module/zfs/metaslab.c b/module/zfs/metaslab.c index d1fee70f004b..ffa88020d803 100644 --- a/module/zfs/metaslab.c +++ b/module/zfs/metaslab.c @@ -2758,7 +2758,8 @@ metaslab_fini_flush_data(metaslab_t *msp) mutex_exit(&spa->spa_flushed_ms_lock); spa_log_sm_decrement_mscount(spa, metaslab_unflushed_txg(msp)); - spa_log_summary_decrement_mscount(spa, metaslab_unflushed_txg(msp)); + spa_log_summary_decrement_mscount(spa, metaslab_unflushed_txg(msp), + metaslab_unflushed_dirty(msp)); } uint64_t @@ -3736,50 +3737,45 @@ metaslab_condense(metaslab_t *msp, dmu_tx_t *tx) metaslab_flush_update(msp, tx); } -/* - * Called when the metaslab has been flushed (its own spacemap now reflects - * all the contents of the pool-wide spacemap log). Updates the metaslab's - * metadata and any pool-wide related log space map data (e.g. summary, - * obsolete logs, etc..) to reflect that. - */ static void -metaslab_flush_update(metaslab_t *msp, dmu_tx_t *tx) +metaslab_unflushed_add(metaslab_t *msp, dmu_tx_t *tx) { - metaslab_group_t *mg = msp->ms_group; - spa_t *spa = mg->mg_vd->vdev_spa; - - ASSERT(MUTEX_HELD(&msp->ms_lock)); - - ASSERT3U(spa_sync_pass(spa), ==, 1); + spa_t *spa = msp->ms_group->mg_vd->vdev_spa; + ASSERT(spa_syncing_log_sm(spa) != NULL); + ASSERT(msp->ms_sm != NULL); ASSERT(range_tree_is_empty(msp->ms_unflushed_allocs)); ASSERT(range_tree_is_empty(msp->ms_unflushed_frees)); - /* - * Just because a metaslab got flushed, that doesn't mean that - * it will pass through metaslab_sync_done(). Thus, make sure to - * update ms_synced_length here in case it doesn't. - */ - msp->ms_synced_length = space_map_length(msp->ms_sm); + mutex_enter(&spa->spa_flushed_ms_lock); + metaslab_set_unflushed_txg(msp, spa_syncing_txg(spa), tx); + metaslab_set_unflushed_dirty(msp, B_TRUE); + avl_add(&spa->spa_metaslabs_by_flushed, msp); + mutex_exit(&spa->spa_flushed_ms_lock); - /* - * We may end up here from metaslab_condense() without the - * feature being active. In that case this is a no-op. - */ - if (!spa_feature_is_active(spa, SPA_FEATURE_LOG_SPACEMAP)) - return; + spa_log_sm_increment_current_mscount(spa); + spa_log_summary_add_flushed_metaslab(spa, B_TRUE); +} +void +metaslab_unflushed_bump(metaslab_t *msp, dmu_tx_t *tx, boolean_t dirty) +{ + spa_t *spa = msp->ms_group->mg_vd->vdev_spa; ASSERT(spa_syncing_log_sm(spa) != NULL); ASSERT(msp->ms_sm != NULL); ASSERT(metaslab_unflushed_txg(msp) != 0); ASSERT3P(avl_find(&spa->spa_metaslabs_by_flushed, msp, NULL), ==, msp); + ASSERT(range_tree_is_empty(msp->ms_unflushed_allocs)); + ASSERT(range_tree_is_empty(msp->ms_unflushed_frees)); VERIFY3U(tx->tx_txg, <=, spa_final_dirty_txg(spa)); /* update metaslab's position in our flushing tree */ uint64_t ms_prev_flushed_txg = metaslab_unflushed_txg(msp); + boolean_t ms_prev_flushed_dirty = metaslab_unflushed_dirty(msp); mutex_enter(&spa->spa_flushed_ms_lock); avl_remove(&spa->spa_metaslabs_by_flushed, msp); metaslab_set_unflushed_txg(msp, spa_syncing_txg(spa), tx); + metaslab_set_unflushed_dirty(msp, dirty); avl_add(&spa->spa_metaslabs_by_flushed, msp); mutex_exit(&spa->spa_flushed_ms_lock); @@ -3787,17 +3783,47 @@ metaslab_flush_update(metaslab_t *msp, dmu_tx_t *tx) spa_log_sm_decrement_mscount(spa, ms_prev_flushed_txg); spa_log_sm_increment_current_mscount(spa); + /* update log space map summary */ + spa_log_summary_decrement_mscount(spa, ms_prev_flushed_txg, + ms_prev_flushed_dirty); + spa_log_summary_add_flushed_metaslab(spa, dirty); + /* cleanup obsolete logs if any */ - uint64_t log_blocks_before = spa_log_sm_nblocks(spa); spa_cleanup_old_sm_logs(spa, tx); - uint64_t log_blocks_after = spa_log_sm_nblocks(spa); - VERIFY3U(log_blocks_after, <=, log_blocks_before); +} - /* update log space map summary */ - uint64_t blocks_gone = log_blocks_before - log_blocks_after; - spa_log_summary_add_flushed_metaslab(spa); - spa_log_summary_decrement_mscount(spa, ms_prev_flushed_txg); - spa_log_summary_decrement_blkcount(spa, blocks_gone); +/* + * Called when the metaslab has been flushed (its own spacemap now reflects + * all the contents of the pool-wide spacemap log). Updates the metaslab's + * metadata and any pool-wide related log space map data (e.g. summary, + * obsolete logs, etc..) to reflect that. + */ +static void +metaslab_flush_update(metaslab_t *msp, dmu_tx_t *tx) +{ + metaslab_group_t *mg = msp->ms_group; + spa_t *spa = mg->mg_vd->vdev_spa; + + ASSERT(MUTEX_HELD(&msp->ms_lock)); + + ASSERT3U(spa_sync_pass(spa), ==, 1); + + /* + * Just because a metaslab got flushed, that doesn't mean that + * it will pass through metaslab_sync_done(). Thus, make sure to + * update ms_synced_length here in case it doesn't. + */ + msp->ms_synced_length = space_map_length(msp->ms_sm); + + /* + * We may end up here from metaslab_condense() without the + * feature being active. In that case this is a no-op. + */ + if (!spa_feature_is_active(spa, SPA_FEATURE_LOG_SPACEMAP) || + metaslab_unflushed_txg(msp) == 0) + return; + + metaslab_unflushed_bump(msp, tx, B_FALSE); } boolean_t @@ -4013,23 +4039,6 @@ metaslab_sync(metaslab_t *msp, uint64_t txg) ASSERT0(metaslab_allocated_space(msp)); } - if (metaslab_unflushed_txg(msp) == 0 && - spa_feature_is_active(spa, SPA_FEATURE_LOG_SPACEMAP)) { - ASSERT(spa_syncing_log_sm(spa) != NULL); - - metaslab_set_unflushed_txg(msp, spa_syncing_txg(spa), tx); - spa_log_sm_increment_current_mscount(spa); - spa_log_summary_add_flushed_metaslab(spa); - - ASSERT(msp->ms_sm != NULL); - mutex_enter(&spa->spa_flushed_ms_lock); - avl_add(&spa->spa_metaslabs_by_flushed, msp); - mutex_exit(&spa->spa_flushed_ms_lock); - - ASSERT(range_tree_is_empty(msp->ms_unflushed_allocs)); - ASSERT(range_tree_is_empty(msp->ms_unflushed_frees)); - } - if (!range_tree_is_empty(msp->ms_checkpointing) && vd->vdev_checkpoint_sm == NULL) { ASSERT(spa_has_checkpoint(spa)); @@ -4077,6 +4086,10 @@ metaslab_sync(metaslab_t *msp, uint64_t txg) space_map_t *log_sm = spa_syncing_log_sm(spa); if (log_sm != NULL) { ASSERT(spa_feature_is_enabled(spa, SPA_FEATURE_LOG_SPACEMAP)); + if (metaslab_unflushed_txg(msp) == 0) + metaslab_unflushed_add(msp, tx); + else if (!metaslab_unflushed_dirty(msp)) + metaslab_unflushed_bump(msp, tx, B_TRUE); space_map_write(log_sm, alloctree, SM_ALLOC, vd->vdev_id, tx); @@ -6139,6 +6152,12 @@ metaslab_enable(metaslab_t *msp, boolean_t sync, boolean_t unload) mutex_exit(&mg->mg_ms_disabled_lock); } +void +metaslab_set_unflushed_dirty(metaslab_t *ms, boolean_t dirty) +{ + ms->ms_unflushed_dirty = dirty; +} + static void metaslab_update_ondisk_flush_data(metaslab_t *ms, dmu_tx_t *tx) { @@ -6175,15 +6194,16 @@ metaslab_update_ondisk_flush_data(metaslab_t *ms, dmu_tx_t *tx) void metaslab_set_unflushed_txg(metaslab_t *ms, uint64_t txg, dmu_tx_t *tx) { - spa_t *spa = ms->ms_group->mg_vd->vdev_spa; - - if (!spa_feature_is_active(spa, SPA_FEATURE_LOG_SPACEMAP)) - return; - ms->ms_unflushed_txg = txg; metaslab_update_ondisk_flush_data(ms, tx); } +boolean_t +metaslab_unflushed_dirty(metaslab_t *ms) +{ + return (ms->ms_unflushed_dirty); +} + uint64_t metaslab_unflushed_txg(metaslab_t *ms) { diff --git a/module/zfs/spa.c b/module/zfs/spa.c index 7546e3e414f1..47f6a3fdd96f 100644 --- a/module/zfs/spa.c +++ b/module/zfs/spa.c @@ -4323,7 +4323,7 @@ spa_ld_load_vdev_metadata(spa_t *spa) error = spa_ld_log_spacemaps(spa); if (error != 0) { - spa_load_failed(spa, "spa_ld_log_sm_data failed [error=%d]", + spa_load_failed(spa, "spa_ld_log_spacemaps failed [error=%d]", error); return (spa_vdev_err(rvd, VDEV_AUX_CORRUPT_DATA, error)); } diff --git a/module/zfs/spa_log_spacemap.c b/module/zfs/spa_log_spacemap.c index 6fd302b8df34..859fa0b3dd18 100644 --- a/module/zfs/spa_log_spacemap.c +++ b/module/zfs/spa_log_spacemap.c @@ -259,6 +259,11 @@ unsigned long zfs_unflushed_log_block_min = 1000; */ unsigned long zfs_unflushed_log_block_max = (1ULL << 18); +/* + * Also we have a hard limit in the size of the log in terms of dirty TXGs. + */ +unsigned long zfs_unflushed_log_txg_max = 1000; + /* * Max # of rows allowed for the log_summary. The tradeoff here is accuracy and * stability of the flushing algorithm (longer summary) vs its runtime overhead @@ -333,9 +338,13 @@ spa_log_sm_set_blocklimit(spa_t *spa) return; } - uint64_t calculated_limit = - (spa_total_metaslabs(spa) * zfs_unflushed_log_block_pct) / 100; - spa->spa_unflushed_stats.sus_blocklimit = MIN(MAX(calculated_limit, + uint64_t msdcount = 0; + for (log_summary_entry_t *e = list_head(&spa->spa_log_summary); + e; e = list_next(&spa->spa_log_summary, e)) + msdcount += e->lse_msdcount; + + uint64_t limit = msdcount * zfs_unflushed_log_block_pct / 100; + spa->spa_unflushed_stats.sus_blocklimit = MIN(MAX(limit, zfs_unflushed_log_block_min), zfs_unflushed_log_block_max); } @@ -380,8 +389,13 @@ spa_log_summary_verify_counts(spa_t *spa) } static boolean_t -summary_entry_is_full(spa_t *spa, log_summary_entry_t *e) +summary_entry_is_full(spa_t *spa, log_summary_entry_t *e, uint64_t txg) { + if (e->lse_end == txg) + return (0); + if (e->lse_txgcount >= DIV_ROUND_UP(zfs_unflushed_log_txg_max, + zfs_max_logsm_summary_length)) + return (1); uint64_t blocks_per_row = MAX(1, DIV_ROUND_UP(spa_log_sm_blocklimit(spa), zfs_max_logsm_summary_length)); @@ -401,7 +415,7 @@ summary_entry_is_full(spa_t *spa, log_summary_entry_t *e) * the metaslab. */ void -spa_log_summary_decrement_mscount(spa_t *spa, uint64_t txg) +spa_log_summary_decrement_mscount(spa_t *spa, uint64_t txg, boolean_t dirty) { /* * We don't track summary data for read-only pools and this function @@ -429,6 +443,8 @@ spa_log_summary_decrement_mscount(spa_t *spa, uint64_t txg) } target->lse_mscount--; + if (dirty) + target->lse_msdcount--; } /* @@ -490,8 +506,10 @@ spa_log_summary_decrement_mscount(spa_t *spa, uint64_t txg) void spa_log_summary_decrement_blkcount(spa_t *spa, uint64_t blocks_gone) { - for (log_summary_entry_t *e = list_head(&spa->spa_log_summary); - e != NULL; e = list_head(&spa->spa_log_summary)) { + log_summary_entry_t *e = list_head(&spa->spa_log_summary); + if (e->lse_txgcount > 0) + e->lse_txgcount--; + for (; e != NULL; e = list_head(&spa->spa_log_summary)) { if (e->lse_blkcount > blocks_gone) { /* * Assert that we stopped at an entry that is not @@ -560,31 +578,52 @@ spa_log_sm_increment_current_mscount(spa_t *spa) static void summary_add_data(spa_t *spa, uint64_t txg, uint64_t metaslabs_flushed, - uint64_t nblocks) + uint64_t metaslabs_dirty, uint64_t nblocks) { log_summary_entry_t *e = list_tail(&spa->spa_log_summary); - if (e == NULL || summary_entry_is_full(spa, e)) { + if (e == NULL || summary_entry_is_full(spa, e, txg)) { e = kmem_zalloc(sizeof (log_summary_entry_t), KM_SLEEP); - e->lse_start = txg; + e->lse_start = e->lse_end = txg; + e->lse_txgcount = 1; list_insert_tail(&spa->spa_log_summary, e); } ASSERT3U(e->lse_start, <=, txg); + if (e->lse_end < txg) { + e->lse_end = txg; + e->lse_txgcount++; + } e->lse_mscount += metaslabs_flushed; + e->lse_msdcount += metaslabs_dirty; e->lse_blkcount += nblocks; } static void spa_log_summary_add_incoming_blocks(spa_t *spa, uint64_t nblocks) { - summary_add_data(spa, spa_syncing_txg(spa), 0, nblocks); + summary_add_data(spa, spa_syncing_txg(spa), 0, 0, nblocks); } void -spa_log_summary_add_flushed_metaslab(spa_t *spa) +spa_log_summary_add_flushed_metaslab(spa_t *spa, boolean_t dirty) { - summary_add_data(spa, spa_syncing_txg(spa), 1, 0); + summary_add_data(spa, spa_syncing_txg(spa), 1, dirty ? 1 : 0, 0); +} + +void +spa_log_summary_dirty_flushed_metaslab(spa_t *spa, uint64_t txg) +{ + log_summary_entry_t *target = NULL; + for (log_summary_entry_t *e = list_head(&spa->spa_log_summary); + e != NULL; e = list_next(&spa->spa_log_summary, e)) { + if (e->lse_start > txg) + break; + target = e; + } + ASSERT3P(target, !=, NULL); + ASSERT3U(target->lse_mscount, !=, 0); + target->lse_msdcount++; } /* @@ -630,6 +669,11 @@ spa_estimate_metaslabs_to_flush(spa_t *spa) int64_t available_blocks = spa_log_sm_blocklimit(spa) - spa_log_sm_nblocks(spa) - incoming; + int64_t available_txgs = zfs_unflushed_log_txg_max; + for (log_summary_entry_t *e = list_head(&spa->spa_log_summary); + e; e = list_next(&spa->spa_log_summary, e)) + available_txgs -= e->lse_txgcount; + /* * This variable tells us the total number of flushes needed to * keep the log size within the limit when we reach txgs_in_future. @@ -637,9 +681,7 @@ spa_estimate_metaslabs_to_flush(spa_t *spa) uint64_t total_flushes = 0; /* Holds the current maximum of our estimates so far. */ - uint64_t max_flushes_pertxg = - MIN(avl_numnodes(&spa->spa_metaslabs_by_flushed), - zfs_min_metaslabs_to_flush); + uint64_t max_flushes_pertxg = zfs_min_metaslabs_to_flush; /* * For our estimations we only look as far in the future @@ -653,11 +695,14 @@ spa_estimate_metaslabs_to_flush(spa_t *spa) * then keep skipping TXGs accumulating more blocks * based on the incoming rate until we exceed it. */ - if (available_blocks >= 0) { - uint64_t skip_txgs = (available_blocks / incoming) + 1; + if (available_blocks >= 0 && available_txgs >= 0) { + uint64_t skip_txgs = MIN(available_txgs + 1, + (available_blocks / incoming) + 1); available_blocks -= (skip_txgs * incoming); + available_txgs -= skip_txgs; txgs_in_future += skip_txgs; ASSERT3S(available_blocks, >=, -incoming); + ASSERT3S(available_txgs, >=, -1); } /* @@ -666,9 +711,10 @@ spa_estimate_metaslabs_to_flush(spa_t *spa) * based on the current entry in the summary, updating * our available_blocks. */ - ASSERT3S(available_blocks, <, 0); + ASSERT(available_blocks < 0 || available_txgs < 0); available_blocks += e->lse_blkcount; - total_flushes += e->lse_mscount; + available_txgs += e->lse_txgcount; + total_flushes += e->lse_msdcount; /* * Keep the running maximum of the total_flushes that @@ -680,8 +726,6 @@ spa_estimate_metaslabs_to_flush(spa_t *spa) */ max_flushes_pertxg = MAX(max_flushes_pertxg, DIV_ROUND_UP(total_flushes, txgs_in_future)); - ASSERT3U(avl_numnodes(&spa->spa_metaslabs_by_flushed), >=, - max_flushes_pertxg); } return (max_flushes_pertxg); } @@ -771,14 +815,11 @@ spa_flush_metaslabs(spa_t *spa, dmu_tx_t *tx) uint64_t want_to_flush; if (spa_flush_all_logs_requested(spa)) { ASSERT3S(spa_state(spa), ==, POOL_STATE_EXPORTED); - want_to_flush = avl_numnodes(&spa->spa_metaslabs_by_flushed); + want_to_flush = UINT64_MAX; } else { want_to_flush = spa_estimate_metaslabs_to_flush(spa); } - ASSERT3U(avl_numnodes(&spa->spa_metaslabs_by_flushed), >=, - want_to_flush); - /* Used purely for verification purposes */ uint64_t visited = 0; @@ -809,31 +850,22 @@ spa_flush_metaslabs(spa_t *spa, dmu_tx_t *tx) if (want_to_flush == 0 && !spa_log_exceeds_memlimit(spa)) break; - mutex_enter(&curr->ms_sync_lock); - mutex_enter(&curr->ms_lock); - boolean_t flushed = metaslab_flush(curr, tx); - mutex_exit(&curr->ms_lock); - mutex_exit(&curr->ms_sync_lock); - - /* - * If we failed to flush a metaslab (because it was loading), - * then we are done with the block heuristic as it's not - * possible to destroy any log space maps once you've skipped - * a metaslab. In that case we just set our counter to 0 but - * we continue looping in case there is still memory pressure - * due to unflushed changes. Note that, flushing a metaslab - * that is not the oldest flushed in the pool, will never - * destroy any log space maps [see spa_cleanup_old_sm_logs()]. - */ - if (!flushed) { - want_to_flush = 0; - } else if (want_to_flush > 0) { - want_to_flush--; - } + if (metaslab_unflushed_dirty(curr)) { + mutex_enter(&curr->ms_sync_lock); + mutex_enter(&curr->ms_lock); + metaslab_flush(curr, tx); + mutex_exit(&curr->ms_lock); + mutex_exit(&curr->ms_sync_lock); + if (want_to_flush > 0) + want_to_flush--; + } else + metaslab_unflushed_bump(curr, tx, B_FALSE); visited++; } ASSERT3U(avl_numnodes(&spa->spa_metaslabs_by_flushed), >=, visited); + + spa_log_sm_set_blocklimit(spa); } /* @@ -904,6 +936,7 @@ spa_cleanup_old_sm_logs(spa_t *spa, dmu_tx_t *tx) avl_remove(&spa->spa_sm_logs_by_txg, sls); space_map_free_obj(mos, sls->sls_sm_obj, tx); VERIFY0(zap_remove_int(mos, spacemap_zap, sls->sls_txg, tx)); + spa_log_summary_decrement_blkcount(spa, sls->sls_nblocks); spa->spa_unflushed_stats.sus_nblocks -= sls->sls_nblocks; kmem_free(sls, sizeof (spa_log_sm_t)); } @@ -963,12 +996,7 @@ spa_generate_syncing_log_sm(spa_t *spa, dmu_tx_t *tx) VERIFY0(space_map_open(&spa->spa_syncing_log_sm, mos, sm_obj, 0, UINT64_MAX, SPA_MINBLOCKSHIFT)); - /* - * If the log space map feature was just enabled, the blocklimit - * has not yet been set. - */ - if (spa_log_sm_blocklimit(spa) == 0) - spa_log_sm_set_blocklimit(spa); + spa_log_sm_set_blocklimit(spa); } /* @@ -1094,12 +1122,18 @@ spa_ld_log_sm_cb(space_map_entry_t *sme, void *arg) panic("invalid maptype_t"); break; } + if (!metaslab_unflushed_dirty(ms)) { + metaslab_set_unflushed_dirty(ms, B_TRUE); + spa_log_summary_dirty_flushed_metaslab(spa, + metaslab_unflushed_txg(ms)); + } return (0); } static int spa_ld_log_sm_data(spa_t *spa) { + spa_log_sm_t *sls, *psls; int error = 0; /* @@ -1113,41 +1147,71 @@ spa_ld_log_sm_data(spa_t *spa) ASSERT0(spa->spa_unflushed_stats.sus_memused); hrtime_t read_logs_starttime = gethrtime(); - /* this is a no-op when we don't have space map logs */ - for (spa_log_sm_t *sls = avl_first(&spa->spa_sm_logs_by_txg); - sls; sls = AVL_NEXT(&spa->spa_sm_logs_by_txg, sls)) { - space_map_t *sm = NULL; - error = space_map_open(&sm, spa_meta_objset(spa), - sls->sls_sm_obj, 0, UINT64_MAX, SPA_MINBLOCKSHIFT); - if (error != 0) { - spa_load_failed(spa, "spa_ld_log_sm_data(): failed at " - "space_map_open(obj=%llu) [error %d]", - (u_longlong_t)sls->sls_sm_obj, error); - goto out; + + /* Prefetch log spacemaps dnodes. */ + for (sls = avl_first(&spa->spa_sm_logs_by_txg); sls; + sls = AVL_NEXT(&spa->spa_sm_logs_by_txg, sls)) { + dmu_prefetch(spa_meta_objset(spa), sls->sls_sm_obj, + 0, 0, 0, ZIO_PRIORITY_SYNC_READ); + } + + uint_t pn = 0; + uint64_t ps = 0; + psls = sls = avl_first(&spa->spa_sm_logs_by_txg); + while (sls != NULL) { + /* Prefetch log spacemaps up to 16 TXGs or MBs ahead. */ + if (psls != NULL && pn < 16 && + (pn < 2 || ps < 2 * dmu_prefetch_max)) { + error = space_map_open(&psls->sls_sm, + spa_meta_objset(spa), psls->sls_sm_obj, 0, + UINT64_MAX, SPA_MINBLOCKSHIFT); + if (error != 0) { + spa_load_failed(spa, "spa_ld_log_sm_data(): " + "failed at space_map_open(obj=%llu) " + "[error %d]", + (u_longlong_t)sls->sls_sm_obj, error); + goto out; + } + dmu_prefetch(spa_meta_objset(spa), psls->sls_sm_obj, + 0, 0, space_map_length(psls->sls_sm), + ZIO_PRIORITY_ASYNC_READ); + pn++; + ps += space_map_length(psls->sls_sm); + psls = AVL_NEXT(&spa->spa_sm_logs_by_txg, psls); + continue; } + /* Load TXG log spacemap into ms_unflushed_allocs/frees. */ + cond_resched(); + ASSERT0(sls->sls_nblocks); + sls->sls_nblocks = space_map_nblocks(sls->sls_sm); + spa->spa_unflushed_stats.sus_nblocks += sls->sls_nblocks; + summary_add_data(spa, sls->sls_txg, + sls->sls_mscount, 0, sls->sls_nblocks); + struct spa_ld_log_sm_arg vla = { .slls_spa = spa, .slls_txg = sls->sls_txg }; - error = space_map_iterate(sm, space_map_length(sm), - spa_ld_log_sm_cb, &vla); + error = space_map_iterate(sls->sls_sm, + space_map_length(sls->sls_sm), spa_ld_log_sm_cb, &vla); if (error != 0) { - space_map_close(sm); spa_load_failed(spa, "spa_ld_log_sm_data(): failed " "at space_map_iterate(obj=%llu) [error %d]", (u_longlong_t)sls->sls_sm_obj, error); goto out; } - ASSERT0(sls->sls_nblocks); - sls->sls_nblocks = space_map_nblocks(sm); - spa->spa_unflushed_stats.sus_nblocks += sls->sls_nblocks; - summary_add_data(spa, sls->sls_txg, - sls->sls_mscount, sls->sls_nblocks); + pn--; + ps -= space_map_length(sls->sls_sm); + space_map_close(sls->sls_sm); + sls->sls_sm = NULL; + sls = AVL_NEXT(&spa->spa_sm_logs_by_txg, sls); - space_map_close(sm); + /* Update log block limits considering just loaded. */ + spa_log_sm_set_blocklimit(spa); } + hrtime_t read_logs_endtime = gethrtime(); spa_load_note(spa, "read %llu log space maps (%llu total blocks - blksz = %llu bytes) " @@ -1157,6 +1221,18 @@ spa_ld_log_sm_data(spa_t *spa) (longlong_t)((read_logs_endtime - read_logs_starttime) / 1000000)); out: + if (error != 0) { + for (spa_log_sm_t *sls = avl_first(&spa->spa_sm_logs_by_txg); + sls; sls = AVL_NEXT(&spa->spa_sm_logs_by_txg, sls)) { + if (sls->sls_sm) { + space_map_close(sls->sls_sm); + sls->sls_sm = NULL; + } + } + } else { + ASSERT0(pn); + ASSERT0(ps); + } /* * Now that the metaslabs contain their unflushed changes: * [1] recalculate their actual allocated space @@ -1237,6 +1313,9 @@ spa_ld_unflushed_txgs(vdev_t *vd) } ms->ms_unflushed_txg = entry.msp_unflushed_txg; + ms->ms_unflushed_dirty = B_FALSE; + ASSERT(range_tree_is_empty(ms->ms_unflushed_allocs)); + ASSERT(range_tree_is_empty(ms->ms_unflushed_frees)); if (ms->ms_unflushed_txg != 0) { mutex_enter(&spa->spa_flushed_ms_lock); avl_add(&spa->spa_metaslabs_by_flushed, ms); @@ -1300,6 +1379,10 @@ ZFS_MODULE_PARAM(zfs, zfs_, unflushed_log_block_min, ULONG, ZMOD_RW, "Lower-bound limit for the maximum amount of blocks allowed in " "log spacemap (see zfs_unflushed_log_block_max)"); +ZFS_MODULE_PARAM(zfs, zfs_, unflushed_log_txg_max, ULONG, ZMOD_RW, + "Hard limit (upper-bound) in the size of the space map log " + "in terms of dirty TXGs."); + ZFS_MODULE_PARAM(zfs, zfs_, unflushed_log_block_pct, ULONG, ZMOD_RW, "Tunable used to determine the number of blocks that can be used for " "the spacemap log, expressed as a percentage of the total number of " diff --git a/module/zfs/vdev.c b/module/zfs/vdev.c index 4a67ba85f58a..fee94b3fff6b 100644 --- a/module/zfs/vdev.c +++ b/module/zfs/vdev.c @@ -1511,13 +1511,6 @@ vdev_metaslab_init(vdev_t *vd, uint64_t txg) if (txg == 0) spa_config_exit(spa, SCL_ALLOC, FTAG); - /* - * Regardless whether this vdev was just added or it is being - * expanded, the metaslab count has changed. Recalculate the - * block limit. - */ - spa_log_sm_set_blocklimit(spa); - return (0); } diff --git a/module/zfs/vdev_removal.c b/module/zfs/vdev_removal.c index f762c1df96aa..4650986efe4d 100644 --- a/module/zfs/vdev_removal.c +++ b/module/zfs/vdev_removal.c @@ -1207,7 +1207,6 @@ vdev_remove_complete(spa_t *spa) vdev_metaslab_fini(vd); metaslab_group_destroy(vd->vdev_mg); vd->vdev_mg = NULL; - spa_log_sm_set_blocklimit(spa); } if (vd->vdev_log_mg != NULL) { ASSERT0(vd->vdev_ms_count); @@ -1935,7 +1934,6 @@ spa_vdev_remove_log(vdev_t *vd, uint64_t *txg) * metaslab_class_histogram_verify() */ vdev_metaslab_fini(vd); - spa_log_sm_set_blocklimit(spa); spa_vdev_config_exit(spa, NULL, *txg, 0, FTAG); *txg = spa_vdev_config_enter(spa);