* CDDL HEADER END
*/
/*
- * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
- * Use is subject to license terms.
+ * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2011 by Delphix. All rights reserved.
*/
#include <sys/zfs_context.h>
-#include <sys/spa_impl.h>
#include <sys/dmu.h>
#include <sys/dmu_tx.h>
#include <sys/space_map.h>
#include <sys/vdev_impl.h>
#include <sys/zio.h>
+#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 or dump device related allocations
+ * to "fast" gang.
+ */
+#define CAN_FASTGANG(flags) \
+ (!((flags) & (METASLAB_GANG_CHILD | METASLAB_GANG_HEADER | \
+ METASLAB_GANG_AVOID)))
+
uint64_t metaslab_aliquot = 512ULL << 10;
uint64_t metaslab_gang_bang = SPA_MAXBLOCKSIZE + 1; /* force gang blocks */
/*
+ * This value defines the number of allowed allocation failures per vdev.
+ * If a device reaches this threshold in a given txg then we consider skipping
+ * allocations on that device.
+ */
+int zfs_mg_alloc_failures;
+
+/*
+ * Metaslab debugging: when set, keeps all space maps in core to verify frees.
+ */
+static int metaslab_debug = 0;
+
+/*
+ * Minimum size which forces the dynamic allocator to change
+ * it's allocation strategy. Once the space map cannot satisfy
+ * 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;
+
+/*
+ * 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
+ * switch to using best-fit allocations.
+ */
+int metaslab_df_free_pct = 4;
+
+/*
+ * A metaslab is considered "free" if it contains a contiguous
+ * segment which is greater than metaslab_min_alloc_size.
+ */
+uint64_t metaslab_min_alloc_size = DMU_MAX_ACCESS;
+
+/*
+ * Max number of space_maps to prefetch.
+ */
+int metaslab_prefetch_limit = SPA_DVAS_PER_BP;
+
+/*
+ * Percentage bonus multiplier for metaslabs that are in the bonus area.
+ */
+int metaslab_smo_bonus_pct = 150;
+
+/*
* ==========================================================================
* Metaslab classes
* ==========================================================================
*/
metaslab_class_t *
-metaslab_class_create(void)
+metaslab_class_create(spa_t *spa, space_map_ops_t *ops)
{
metaslab_class_t *mc;
mc = kmem_zalloc(sizeof (metaslab_class_t), KM_SLEEP);
+ mc->mc_spa = spa;
mc->mc_rotor = NULL;
+ mc->mc_ops = ops;
return (mc);
}
void
metaslab_class_destroy(metaslab_class_t *mc)
{
- metaslab_group_t *mg;
-
- while ((mg = mc->mc_rotor) != NULL) {
- metaslab_class_remove(mc, mg);
- metaslab_group_destroy(mg);
- }
+ ASSERT(mc->mc_rotor == NULL);
+ ASSERT(mc->mc_alloc == 0);
+ ASSERT(mc->mc_deferred == 0);
+ ASSERT(mc->mc_space == 0);
+ ASSERT(mc->mc_dspace == 0);
kmem_free(mc, sizeof (metaslab_class_t));
}
-void
-metaslab_class_add(metaslab_class_t *mc, metaslab_group_t *mg)
+int
+metaslab_class_validate(metaslab_class_t *mc)
{
- metaslab_group_t *mgprev, *mgnext;
+ metaslab_group_t *mg;
+ vdev_t *vd;
- ASSERT(mg->mg_class == NULL);
+ /*
+ * Must hold one of the spa_config locks.
+ */
+ ASSERT(spa_config_held(mc->mc_spa, SCL_ALL, RW_READER) ||
+ spa_config_held(mc->mc_spa, SCL_ALL, RW_WRITER));
- if ((mgprev = mc->mc_rotor) == NULL) {
- mg->mg_prev = mg;
- mg->mg_next = mg;
- } else {
- mgnext = mgprev->mg_next;
- mg->mg_prev = mgprev;
- mg->mg_next = mgnext;
- mgprev->mg_next = mg;
- mgnext->mg_prev = mg;
- }
- mc->mc_rotor = mg;
- mg->mg_class = mc;
+ if ((mg = mc->mc_rotor) == NULL)
+ return (0);
+
+ do {
+ vd = mg->mg_vd;
+ ASSERT(vd->vdev_mg != NULL);
+ ASSERT3P(vd->vdev_top, ==, vd);
+ ASSERT3P(mg->mg_class, ==, mc);
+ ASSERT3P(vd->vdev_ops, !=, &vdev_hole_ops);
+ } while ((mg = mg->mg_next) != mc->mc_rotor);
+
+ return (0);
}
void
-metaslab_class_remove(metaslab_class_t *mc, metaslab_group_t *mg)
+metaslab_class_space_update(metaslab_class_t *mc, int64_t alloc_delta,
+ int64_t defer_delta, int64_t space_delta, int64_t dspace_delta)
{
- metaslab_group_t *mgprev, *mgnext;
+ atomic_add_64(&mc->mc_alloc, alloc_delta);
+ atomic_add_64(&mc->mc_deferred, defer_delta);
+ atomic_add_64(&mc->mc_space, space_delta);
+ atomic_add_64(&mc->mc_dspace, dspace_delta);
+}
- ASSERT(mg->mg_class == mc);
+uint64_t
+metaslab_class_get_alloc(metaslab_class_t *mc)
+{
+ return (mc->mc_alloc);
+}
- mgprev = mg->mg_prev;
- mgnext = mg->mg_next;
+uint64_t
+metaslab_class_get_deferred(metaslab_class_t *mc)
+{
+ return (mc->mc_deferred);
+}
- if (mg == mgnext) {
- mc->mc_rotor = NULL;
- } else {
- mc->mc_rotor = mgnext;
- mgprev->mg_next = mgnext;
- mgnext->mg_prev = mgprev;
- }
+uint64_t
+metaslab_class_get_space(metaslab_class_t *mc)
+{
+ return (mc->mc_space);
+}
- mg->mg_prev = NULL;
- mg->mg_next = NULL;
- mg->mg_class = NULL;
+uint64_t
+metaslab_class_get_dspace(metaslab_class_t *mc)
+{
+ return (spa_deflate(mc->mc_spa) ? mc->mc_dspace : mc->mc_space);
}
/*
mutex_init(&mg->mg_lock, NULL, MUTEX_DEFAULT, NULL);
avl_create(&mg->mg_metaslab_tree, metaslab_compare,
sizeof (metaslab_t), offsetof(struct metaslab, ms_group_node));
- mg->mg_aliquot = metaslab_aliquot * MAX(1, vd->vdev_children);
mg->mg_vd = vd;
- metaslab_class_add(mc, mg);
+ mg->mg_class = mc;
+ mg->mg_activation_count = 0;
return (mg);
}
void
metaslab_group_destroy(metaslab_group_t *mg)
{
+ ASSERT(mg->mg_prev == NULL);
+ ASSERT(mg->mg_next == NULL);
+ /*
+ * We may have gone below zero with the activation count
+ * either because we never activated in the first place or
+ * because we're done, and possibly removing the vdev.
+ */
+ ASSERT(mg->mg_activation_count <= 0);
+
avl_destroy(&mg->mg_metaslab_tree);
mutex_destroy(&mg->mg_lock);
kmem_free(mg, sizeof (metaslab_group_t));
}
+void
+metaslab_group_activate(metaslab_group_t *mg)
+{
+ metaslab_class_t *mc = mg->mg_class;
+ metaslab_group_t *mgprev, *mgnext;
+
+ ASSERT(spa_config_held(mc->mc_spa, SCL_ALLOC, RW_WRITER));
+
+ ASSERT(mc->mc_rotor != mg);
+ ASSERT(mg->mg_prev == NULL);
+ ASSERT(mg->mg_next == NULL);
+ ASSERT(mg->mg_activation_count <= 0);
+
+ if (++mg->mg_activation_count <= 0)
+ return;
+
+ mg->mg_aliquot = metaslab_aliquot * MAX(1, mg->mg_vd->vdev_children);
+
+ if ((mgprev = mc->mc_rotor) == NULL) {
+ mg->mg_prev = mg;
+ mg->mg_next = mg;
+ } else {
+ mgnext = mgprev->mg_next;
+ mg->mg_prev = mgprev;
+ mg->mg_next = mgnext;
+ mgprev->mg_next = mg;
+ mgnext->mg_prev = mg;
+ }
+ mc->mc_rotor = mg;
+}
+
+void
+metaslab_group_passivate(metaslab_group_t *mg)
+{
+ metaslab_class_t *mc = mg->mg_class;
+ metaslab_group_t *mgprev, *mgnext;
+
+ ASSERT(spa_config_held(mc->mc_spa, SCL_ALLOC, RW_WRITER));
+
+ if (--mg->mg_activation_count != 0) {
+ ASSERT(mc->mc_rotor != mg);
+ ASSERT(mg->mg_prev == NULL);
+ ASSERT(mg->mg_next == NULL);
+ ASSERT(mg->mg_activation_count < 0);
+ return;
+ }
+
+ mgprev = mg->mg_prev;
+ mgnext = mg->mg_next;
+
+ if (mg == mgnext) {
+ mc->mc_rotor = NULL;
+ } else {
+ mc->mc_rotor = mgnext;
+ mgprev->mg_next = mgnext;
+ mgnext->mg_prev = mgprev;
+ }
+
+ mg->mg_prev = NULL;
+ mg->mg_next = NULL;
+}
+
static void
metaslab_group_add(metaslab_group_t *mg, metaslab_t *msp)
{
/*
* ==========================================================================
- * The first-fit block allocator
+ * Common allocator routines
* ==========================================================================
*/
-static void
-metaslab_ff_load(space_map_t *sm)
+static int
+metaslab_segsize_compare(const void *x1, const void *x2)
{
- ASSERT(sm->sm_ppd == NULL);
- sm->sm_ppd = kmem_zalloc(64 * sizeof (uint64_t), KM_SLEEP);
-}
+ const space_seg_t *s1 = x1;
+ const space_seg_t *s2 = x2;
+ uint64_t ss_size1 = s1->ss_end - s1->ss_start;
+ uint64_t ss_size2 = s2->ss_end - s2->ss_start;
-static void
-metaslab_ff_unload(space_map_t *sm)
-{
- kmem_free(sm->sm_ppd, 64 * sizeof (uint64_t));
- sm->sm_ppd = NULL;
+ if (ss_size1 < ss_size2)
+ return (-1);
+ if (ss_size1 > ss_size2)
+ return (1);
+
+ if (s1->ss_start < s2->ss_start)
+ return (-1);
+ if (s1->ss_start > s2->ss_start)
+ return (1);
+
+ return (0);
}
+#if defined(WITH_FF_BLOCK_ALLOCATOR) || \
+ defined(WITH_DF_BLOCK_ALLOCATOR) || \
+ defined(WITH_CDF_BLOCK_ALLOCATOR)
+/*
+ * This is a helper function that can be used by the allocator to find
+ * a suitable block to allocate. This will search the specified AVL
+ * tree looking for a block that matches the specified criteria.
+ */
static uint64_t
-metaslab_ff_alloc(space_map_t *sm, uint64_t size)
+metaslab_block_picker(avl_tree_t *t, uint64_t *cursor, uint64_t size,
+ uint64_t align)
{
- avl_tree_t *t = &sm->sm_root;
- uint64_t align = size & -size;
- uint64_t *cursor = (uint64_t *)sm->sm_ppd + highbit(align) - 1;
space_seg_t *ss, ssearch;
avl_index_t where;
return (-1ULL);
*cursor = 0;
- return (metaslab_ff_alloc(sm, size));
+ return (metaslab_block_picker(t, cursor, size, align));
+}
+#endif /* WITH_FF/DF/CDF_BLOCK_ALLOCATOR */
+
+static void
+metaslab_pp_load(space_map_t *sm)
+{
+ space_seg_t *ss;
+
+ ASSERT(sm->sm_ppd == NULL);
+ sm->sm_ppd = kmem_zalloc(64 * sizeof (uint64_t), KM_SLEEP);
+
+ sm->sm_pp_root = kmem_alloc(sizeof (avl_tree_t), KM_SLEEP);
+ avl_create(sm->sm_pp_root, metaslab_segsize_compare,
+ sizeof (space_seg_t), offsetof(struct space_seg, ss_pp_node));
+
+ for (ss = avl_first(&sm->sm_root); ss; ss = AVL_NEXT(&sm->sm_root, ss))
+ avl_add(sm->sm_pp_root, ss);
+}
+
+static void
+metaslab_pp_unload(space_map_t *sm)
+{
+ void *cookie = NULL;
+
+ kmem_free(sm->sm_ppd, 64 * sizeof (uint64_t));
+ sm->sm_ppd = NULL;
+
+ while (avl_destroy_nodes(sm->sm_pp_root, &cookie) != NULL) {
+ /* tear down the tree */
+ }
+
+ avl_destroy(sm->sm_pp_root);
+ kmem_free(sm->sm_pp_root, sizeof (avl_tree_t));
+ sm->sm_pp_root = NULL;
}
/* ARGSUSED */
static void
-metaslab_ff_claim(space_map_t *sm, uint64_t start, uint64_t size)
+metaslab_pp_claim(space_map_t *sm, uint64_t start, uint64_t size)
{
/* No need to update cursor */
}
/* ARGSUSED */
static void
-metaslab_ff_free(space_map_t *sm, uint64_t start, uint64_t size)
+metaslab_pp_free(space_map_t *sm, uint64_t start, uint64_t size)
{
/* No need to update cursor */
}
+/*
+ * Return the maximum contiguous segment within the metaslab.
+ */
+uint64_t
+metaslab_pp_maxsize(space_map_t *sm)
+{
+ avl_tree_t *t = sm->sm_pp_root;
+ space_seg_t *ss;
+
+ if (t == NULL || (ss = avl_last(t)) == NULL)
+ return (0ULL);
+
+ return (ss->ss_end - ss->ss_start);
+}
+
+#if defined(WITH_FF_BLOCK_ALLOCATOR)
+/*
+ * ==========================================================================
+ * The first-fit block allocator
+ * ==========================================================================
+ */
+static uint64_t
+metaslab_ff_alloc(space_map_t *sm, uint64_t size)
+{
+ avl_tree_t *t = &sm->sm_root;
+ uint64_t align = size & -size;
+ uint64_t *cursor = (uint64_t *)sm->sm_ppd + highbit(align) - 1;
+
+ return (metaslab_block_picker(t, cursor, size, align));
+}
+
+/* ARGSUSED */
+boolean_t
+metaslab_ff_fragmented(space_map_t *sm)
+{
+ return (B_TRUE);
+}
+
static space_map_ops_t metaslab_ff_ops = {
- metaslab_ff_load,
- metaslab_ff_unload,
+ metaslab_pp_load,
+ metaslab_pp_unload,
metaslab_ff_alloc,
- metaslab_ff_claim,
- metaslab_ff_free
+ metaslab_pp_claim,
+ metaslab_pp_free,
+ metaslab_pp_maxsize,
+ metaslab_ff_fragmented
+};
+
+space_map_ops_t *zfs_metaslab_ops = &metaslab_ff_ops;
+#endif /* WITH_FF_BLOCK_ALLOCATOR */
+
+#if defined(WITH_DF_BLOCK_ALLOCATOR)
+/*
+ * ==========================================================================
+ * Dynamic block allocator -
+ * Uses the first fit allocation scheme until space get low and then
+ * adjusts to a best fit allocation method. Uses metaslab_df_alloc_threshold
+ * and metaslab_df_free_pct to determine when to switch the allocation scheme.
+ * ==========================================================================
+ */
+static uint64_t
+metaslab_df_alloc(space_map_t *sm, uint64_t size)
+{
+ avl_tree_t *t = &sm->sm_root;
+ uint64_t align = size & -size;
+ uint64_t *cursor = (uint64_t *)sm->sm_ppd + highbit(align) - 1;
+ uint64_t max_size = metaslab_pp_maxsize(sm);
+ int free_pct = sm->sm_space * 100 / sm->sm_size;
+
+ ASSERT(MUTEX_HELD(sm->sm_lock));
+ ASSERT3U(avl_numnodes(&sm->sm_root), ==, avl_numnodes(sm->sm_pp_root));
+
+ if (max_size < size)
+ return (-1ULL);
+
+ /*
+ * If we're running low on space switch to using the size
+ * sorted AVL tree (best-fit).
+ */
+ if (max_size < metaslab_df_alloc_threshold ||
+ free_pct < metaslab_df_free_pct) {
+ t = sm->sm_pp_root;
+ *cursor = 0;
+ }
+
+ return (metaslab_block_picker(t, cursor, size, 1ULL));
+}
+
+static boolean_t
+metaslab_df_fragmented(space_map_t *sm)
+{
+ uint64_t max_size = metaslab_pp_maxsize(sm);
+ int free_pct = sm->sm_space * 100 / sm->sm_size;
+
+ if (max_size >= metaslab_df_alloc_threshold &&
+ free_pct >= metaslab_df_free_pct)
+ return (B_FALSE);
+
+ return (B_TRUE);
+}
+
+static space_map_ops_t metaslab_df_ops = {
+ metaslab_pp_load,
+ metaslab_pp_unload,
+ metaslab_df_alloc,
+ metaslab_pp_claim,
+ metaslab_pp_free,
+ metaslab_pp_maxsize,
+ metaslab_df_fragmented
+};
+
+space_map_ops_t *zfs_metaslab_ops = &metaslab_df_ops;
+#endif /* WITH_DF_BLOCK_ALLOCATOR */
+
+/*
+ * ==========================================================================
+ * Other experimental allocators
+ * ==========================================================================
+ */
+#if defined(WITH_CDF_BLOCK_ALLOCATOR)
+static uint64_t
+metaslab_cdf_alloc(space_map_t *sm, uint64_t size)
+{
+ avl_tree_t *t = &sm->sm_root;
+ uint64_t *cursor = (uint64_t *)sm->sm_ppd;
+ uint64_t *extent_end = (uint64_t *)sm->sm_ppd + 1;
+ uint64_t max_size = metaslab_pp_maxsize(sm);
+ uint64_t rsize = size;
+ uint64_t offset = 0;
+
+ ASSERT(MUTEX_HELD(sm->sm_lock));
+ ASSERT3U(avl_numnodes(&sm->sm_root), ==, avl_numnodes(sm->sm_pp_root));
+
+ if (max_size < size)
+ return (-1ULL);
+
+ ASSERT3U(*extent_end, >=, *cursor);
+
+ /*
+ * If we're running low on space switch to using the size
+ * sorted AVL tree (best-fit).
+ */
+ if ((*cursor + size) > *extent_end) {
+
+ t = sm->sm_pp_root;
+ *cursor = *extent_end = 0;
+
+ if (max_size > 2 * SPA_MAXBLOCKSIZE)
+ rsize = MIN(metaslab_min_alloc_size, max_size);
+ offset = metaslab_block_picker(t, extent_end, rsize, 1ULL);
+ if (offset != -1)
+ *cursor = offset + size;
+ } else {
+ offset = metaslab_block_picker(t, cursor, rsize, 1ULL);
+ }
+ ASSERT3U(*cursor, <=, *extent_end);
+ return (offset);
+}
+
+static boolean_t
+metaslab_cdf_fragmented(space_map_t *sm)
+{
+ uint64_t max_size = metaslab_pp_maxsize(sm);
+
+ if (max_size > (metaslab_min_alloc_size * 10))
+ return (B_FALSE);
+ return (B_TRUE);
+}
+
+static space_map_ops_t metaslab_cdf_ops = {
+ metaslab_pp_load,
+ metaslab_pp_unload,
+ metaslab_cdf_alloc,
+ metaslab_pp_claim,
+ metaslab_pp_free,
+ metaslab_pp_maxsize,
+ metaslab_cdf_fragmented
+};
+
+space_map_ops_t *zfs_metaslab_ops = &metaslab_cdf_ops;
+#endif /* WITH_CDF_BLOCK_ALLOCATOR */
+
+#if defined(WITH_NDF_BLOCK_ALLOCATOR)
+uint64_t metaslab_ndf_clump_shift = 4;
+
+static uint64_t
+metaslab_ndf_alloc(space_map_t *sm, uint64_t size)
+{
+ avl_tree_t *t = &sm->sm_root;
+ avl_index_t where;
+ space_seg_t *ss, ssearch;
+ uint64_t hbit = highbit(size);
+ uint64_t *cursor = (uint64_t *)sm->sm_ppd + hbit - 1;
+ uint64_t max_size = metaslab_pp_maxsize(sm);
+
+ ASSERT(MUTEX_HELD(sm->sm_lock));
+ ASSERT3U(avl_numnodes(&sm->sm_root), ==, avl_numnodes(sm->sm_pp_root));
+
+ if (max_size < size)
+ return (-1ULL);
+
+ ssearch.ss_start = *cursor;
+ ssearch.ss_end = *cursor + size;
+
+ ss = avl_find(t, &ssearch, &where);
+ if (ss == NULL || (ss->ss_start + size > ss->ss_end)) {
+ t = sm->sm_pp_root;
+
+ ssearch.ss_start = 0;
+ ssearch.ss_end = MIN(max_size,
+ 1ULL << (hbit + metaslab_ndf_clump_shift));
+ ss = avl_find(t, &ssearch, &where);
+ if (ss == NULL)
+ ss = avl_nearest(t, where, AVL_AFTER);
+ ASSERT(ss != NULL);
+ }
+
+ if (ss != NULL) {
+ if (ss->ss_start + size <= ss->ss_end) {
+ *cursor = ss->ss_start + size;
+ return (ss->ss_start);
+ }
+ }
+ return (-1ULL);
+}
+
+static boolean_t
+metaslab_ndf_fragmented(space_map_t *sm)
+{
+ uint64_t max_size = metaslab_pp_maxsize(sm);
+
+ if (max_size > (metaslab_min_alloc_size << metaslab_ndf_clump_shift))
+ return (B_FALSE);
+ return (B_TRUE);
+}
+
+
+static space_map_ops_t metaslab_ndf_ops = {
+ metaslab_pp_load,
+ metaslab_pp_unload,
+ metaslab_ndf_alloc,
+ metaslab_pp_claim,
+ metaslab_pp_free,
+ metaslab_pp_maxsize,
+ metaslab_ndf_fragmented
};
+space_map_ops_t *zfs_metaslab_ops = &metaslab_ndf_ops;
+#endif /* WITH_NDF_BLOCK_ALLOCATOR */
+
/*
* ==========================================================================
* Metaslabs
metaslab_group_add(mg, msp);
+ if (metaslab_debug && smo->smo_object != 0) {
+ mutex_enter(&msp->ms_lock);
+ VERIFY(space_map_load(&msp->ms_map, mg->mg_class->mc_ops,
+ SM_FREE, smo, spa_meta_objset(vd->vdev_spa)) == 0);
+ mutex_exit(&msp->ms_lock);
+ }
+
/*
* If we're opening an existing pool (txg == 0) or creating
* a new one (txg == TXG_INITIAL), all space is available now.
metaslab_sync_done(msp, 0);
if (txg != 0) {
- /*
- * The vdev is dirty, but the metaslab isn't -- it just needs
- * to have metaslab_sync_done() invoked from vdev_sync_done().
- * [We could just dirty the metaslab, but that would cause us
- * to allocate a space map object for it, which is wasteful
- * and would mess up the locality logic in metaslab_weight().]
- */
- ASSERT(TXG_CLEAN(txg) == spa_last_synced_txg(vd->vdev_spa));
vdev_dirty(vd, 0, NULL, txg);
- vdev_dirty(vd, VDD_METASLAB, msp, TXG_CLEAN(txg));
+ vdev_dirty(vd, VDD_METASLAB, msp, txg);
}
return (msp);
metaslab_group_t *mg = msp->ms_group;
int t;
- vdev_space_update(mg->mg_vd, -msp->ms_map.sm_size,
- -msp->ms_smo.smo_alloc, B_TRUE);
+ vdev_space_update(mg->mg_vd,
+ -msp->ms_smo.smo_alloc, 0, -msp->ms_map.sm_size);
metaslab_group_remove(mg, msp);
space_map_destroy(&msp->ms_freemap[t]);
}
+ for (t = 0; t < TXG_DEFER_SIZE; t++)
+ space_map_destroy(&msp->ms_defermap[t]);
+
+ ASSERT3S(msp->ms_deferspace, ==, 0);
+
mutex_exit(&msp->ms_lock);
mutex_destroy(&msp->ms_lock);
#define METASLAB_WEIGHT_SECONDARY (1ULL << 62)
#define METASLAB_ACTIVE_MASK \
(METASLAB_WEIGHT_PRIMARY | METASLAB_WEIGHT_SECONDARY)
-#define METASLAB_SMO_BONUS_MULTIPLIER 2
static uint64_t
metaslab_weight(metaslab_t *msp)
ASSERT(weight >= space && weight <= 2 * space);
/*
- * For locality, assign higher weight to metaslabs we've used before.
+ * For locality, assign higher weight to metaslabs which have
+ * a lower offset than what we've already activated.
*/
- if (smo->smo_object != 0)
- weight *= METASLAB_SMO_BONUS_MULTIPLIER;
+ if (sm->sm_start <= mg->mg_bonus_area)
+ weight *= (metaslab_smo_bonus_pct / 100);
ASSERT(weight >= space &&
- weight <= 2 * METASLAB_SMO_BONUS_MULTIPLIER * space);
+ weight <= 2 * (metaslab_smo_bonus_pct / 100) * space);
+
+ if (sm->sm_loaded && !sm->sm_ops->smop_fragmented(sm)) {
+ /*
+ * If this metaslab is one we're actively using, adjust its
+ * weight to make it preferable to any inactive metaslab so
+ * we'll polish it off.
+ */
+ weight |= (msp->ms_weight & METASLAB_ACTIVE_MASK);
+ }
+ return (weight);
+}
+
+static void
+metaslab_prefetch(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;
+
+ mutex_enter(&mg->mg_lock);
/*
- * If this metaslab is one we're actively using, adjust its weight to
- * make it preferable to any inactive metaslab so we'll polish it off.
+ * Prefetch the next potential metaslabs
*/
- weight |= (msp->ms_weight & METASLAB_ACTIVE_MASK);
+ for (msp = avl_first(t), m = 0; msp; msp = AVL_NEXT(t, msp), m++) {
+ space_map_t *sm = &msp->ms_map;
+ space_map_obj_t *smo = &msp->ms_smo;
- return (weight);
+ /* If we have reached our prefetch limit then we're done */
+ if (m >= metaslab_prefetch_limit)
+ break;
+
+ if (!sm->sm_loaded && smo->smo_object != 0) {
+ mutex_exit(&mg->mg_lock);
+ dmu_prefetch(spa_meta_objset(spa), smo->smo_object,
+ 0ULL, smo->smo_objsize);
+ mutex_enter(&mg->mg_lock);
+ }
+ }
+ mutex_exit(&mg->mg_lock);
}
static int
metaslab_activate(metaslab_t *msp, uint64_t activation_weight)
{
+ metaslab_group_t *mg = msp->ms_group;
space_map_t *sm = &msp->ms_map;
+ space_map_ops_t *sm_ops = msp->ms_group->mg_class->mc_ops;
+ int t;
ASSERT(MUTEX_HELD(&msp->ms_lock));
if ((msp->ms_weight & METASLAB_ACTIVE_MASK) == 0) {
- int error = space_map_load(sm, &metaslab_ff_ops,
- SM_FREE, &msp->ms_smo,
- msp->ms_group->mg_vd->vdev_spa->spa_meta_objset);
- if (error) {
- metaslab_group_sort(msp->ms_group, msp, 0);
- return (error);
+ space_map_load_wait(sm);
+ if (!sm->sm_loaded) {
+ int error = space_map_load(sm, sm_ops, SM_FREE,
+ &msp->ms_smo,
+ spa_meta_objset(msp->ms_group->mg_vd->vdev_spa));
+ if (error) {
+ metaslab_group_sort(msp->ms_group, msp, 0);
+ return (error);
+ }
+ for (t = 0; t < TXG_DEFER_SIZE; t++)
+ space_map_walk(&msp->ms_defermap[t],
+ space_map_claim, sm);
+
}
+
+ /*
+ * Track the bonus area as we activate new metaslabs.
+ */
+ if (sm->sm_start > mg->mg_bonus_area) {
+ mutex_enter(&mg->mg_lock);
+ mg->mg_bonus_area = sm->sm_start;
+ mutex_exit(&mg->mg_lock);
+ }
+
metaslab_group_sort(msp->ms_group, msp,
msp->ms_weight | activation_weight);
}
{
vdev_t *vd = msp->ms_group->mg_vd;
spa_t *spa = vd->vdev_spa;
- objset_t *mos = spa->spa_meta_objset;
+ objset_t *mos = spa_meta_objset(spa);
space_map_t *allocmap = &msp->ms_allocmap[txg & TXG_MASK];
space_map_t *freemap = &msp->ms_freemap[txg & TXG_MASK];
space_map_t *freed_map = &msp->ms_freemap[TXG_CLEAN(txg) & TXG_MASK];
dmu_tx_t *tx;
int t;
- tx = dmu_tx_create_assigned(spa_get_dsl(spa), txg);
+ ASSERT(!vd->vdev_ishole);
+
+ if (allocmap->sm_space == 0 && freemap->sm_space == 0)
+ return;
/*
* The only state that can actually be changing concurrently with
* 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);
+
+ tx = dmu_tx_create_assigned(spa_get_dsl(spa), txg);
if (smo->smo_object == 0) {
ASSERT(smo->smo_objsize == 0);
ASSERT(smo->smo_alloc == 0);
- mutex_exit(&msp->ms_lock);
smo->smo_object = dmu_object_alloc(mos,
DMU_OT_SPACE_MAP, 1 << SPACE_MAP_BLOCKSHIFT,
DMU_OT_SPACE_MAP_HEADER, sizeof (*smo), tx);
dmu_write(mos, vd->vdev_ms_array, sizeof (uint64_t) *
(sm->sm_start >> vd->vdev_ms_shift),
sizeof (uint64_t), &smo->smo_object, tx);
- mutex_enter(&msp->ms_lock);
}
+ mutex_enter(&msp->ms_lock);
+
space_map_walk(freemap, space_map_add, freed_map);
if (sm->sm_loaded && spa_sync_pass(spa) == 1 && smo->smo_objsize >=
* This metaslab is 100% allocated,
* minus the content of the in-core map (sm),
* minus what's been freed this txg (freed_map),
+ * minus deferred frees (ms_defermap[]),
* minus allocations from txgs in the future
* (because they haven't been committed yet).
*/
space_map_walk(sm, space_map_remove, allocmap);
space_map_walk(freed_map, space_map_remove, allocmap);
+ for (t = 0; t < TXG_DEFER_SIZE; t++)
+ space_map_walk(&msp->ms_defermap[t],
+ space_map_remove, allocmap);
+
for (t = 1; t < TXG_CONCURRENT_STATES; t++)
space_map_walk(&msp->ms_allocmap[(txg + t) & TXG_MASK],
space_map_remove, allocmap);
space_map_obj_t *smosync = &msp->ms_smo_syncing;
space_map_t *sm = &msp->ms_map;
space_map_t *freed_map = &msp->ms_freemap[TXG_CLEAN(txg) & TXG_MASK];
+ space_map_t *defer_map = &msp->ms_defermap[txg % TXG_DEFER_SIZE];
metaslab_group_t *mg = msp->ms_group;
vdev_t *vd = mg->mg_vd;
+ int64_t alloc_delta, defer_delta;
int t;
+ ASSERT(!vd->vdev_ishole);
+
mutex_enter(&msp->ms_lock);
/*
space_map_create(&msp->ms_freemap[t], sm->sm_start,
sm->sm_size, sm->sm_shift, sm->sm_lock);
}
- vdev_space_update(vd, sm->sm_size, 0, B_TRUE);
+
+ for (t = 0; t < TXG_DEFER_SIZE; t++)
+ space_map_create(&msp->ms_defermap[t], sm->sm_start,
+ sm->sm_size, sm->sm_shift, sm->sm_lock);
+
+ vdev_space_update(vd, 0, 0, sm->sm_size);
}
- vdev_space_update(vd, 0, smosync->smo_alloc - smo->smo_alloc, B_TRUE);
+ alloc_delta = smosync->smo_alloc - smo->smo_alloc;
+ defer_delta = freed_map->sm_space - defer_map->sm_space;
+
+ vdev_space_update(vd, alloc_delta + defer_delta, defer_delta, 0);
ASSERT(msp->ms_allocmap[txg & TXG_MASK].sm_space == 0);
ASSERT(msp->ms_freemap[txg & TXG_MASK].sm_space == 0);
/*
* If there's a space_map_load() in progress, wait for it to complete
* so that we have a consistent view of the in-core space map.
- * Then, add everything we freed in this txg to the map.
+ * Then, add defer_map (oldest deferred frees) to this map and
+ * transfer freed_map (this txg's frees) to defer_map.
*/
space_map_load_wait(sm);
- space_map_vacate(freed_map, sm->sm_loaded ? space_map_free : NULL, sm);
+ space_map_vacate(defer_map, sm->sm_loaded ? space_map_free : NULL, sm);
+ space_map_vacate(freed_map, space_map_add, defer_map);
*smo = *smosync;
+ msp->ms_deferspace += defer_delta;
+ ASSERT3S(msp->ms_deferspace, >=, 0);
+ ASSERT3S(msp->ms_deferspace, <=, sm->sm_size);
+ if (msp->ms_deferspace != 0) {
+ /*
+ * Keep syncing this metaslab until all deferred frees
+ * are back in circulation.
+ */
+ vdev_dirty(vd, VDD_METASLAB, msp, txg + 1);
+ }
+
/*
* If the map is loaded but no longer active, evict it as soon as all
* future allocations have synced. (If we unloaded it now and then
if (msp->ms_allocmap[(txg + t) & TXG_MASK].sm_space)
evictable = 0;
- if (evictable)
+ if (evictable && !metaslab_debug)
space_map_unload(sm);
}
mutex_exit(&msp->ms_lock);
}
+void
+metaslab_sync_reassess(metaslab_group_t *mg)
+{
+ vdev_t *vd = mg->mg_vd;
+ int64_t failures = mg->mg_alloc_failures;
+ int m;
+
+ /*
+ * Re-evaluate all metaslabs which have lower offsets than the
+ * bonus area.
+ */
+ for (m = 0; m < vd->vdev_ms_count; m++) {
+ metaslab_t *msp = vd->vdev_ms[m];
+
+ if (msp->ms_map.sm_start > mg->mg_bonus_area)
+ break;
+
+ mutex_enter(&msp->ms_lock);
+ metaslab_group_sort(mg, msp, metaslab_weight(msp));
+ mutex_exit(&msp->ms_lock);
+ }
+
+ atomic_add_64(&mg->mg_alloc_failures, -failures);
+
+ /*
+ * Prefetch the next potential metaslabs
+ */
+ metaslab_prefetch(mg);
+}
+
static uint64_t
metaslab_distance(metaslab_t *msp, dva_t *dva)
{
}
static uint64_t
-metaslab_group_alloc(metaslab_group_t *mg, uint64_t size, uint64_t txg,
- uint64_t min_distance, dva_t *dva, int d)
+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, int flags)
{
+ spa_t *spa = mg->mg_vd->vdev_spa;
metaslab_t *msp = NULL;
uint64_t offset = -1ULL;
avl_tree_t *t = &mg->mg_metaslab_tree;
int i;
activation_weight = METASLAB_WEIGHT_PRIMARY;
- for (i = 0; i < d; i++)
- if (DVA_GET_VDEV(&dva[i]) == mg->mg_vd->vdev_id)
+ for (i = 0; i < d; i++) {
+ if (DVA_GET_VDEV(&dva[i]) == mg->mg_vd->vdev_id) {
activation_weight = METASLAB_WEIGHT_SECONDARY;
+ break;
+ }
+ }
for (;;) {
+ boolean_t was_active;
+
mutex_enter(&mg->mg_lock);
for (msp = avl_first(t); msp; msp = AVL_NEXT(t, msp)) {
- if (msp->ms_weight < size) {
+ 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, "
+ "failures %llu, weight %llu",
+ spa_name(spa), mg->mg_vd->vdev_id, txg,
+ mg, msp, psize, asize,
+ mg->mg_alloc_failures, msp->ms_weight);
mutex_exit(&mg->mg_lock);
return (-1ULL);
}
-
+ was_active = msp->ms_weight & METASLAB_ACTIVE_MASK;
if (activation_weight == METASLAB_WEIGHT_PRIMARY)
break;
if (msp == NULL)
return (-1ULL);
+ /*
+ * If we've already reached the allowable number of failed
+ * allocation attempts on this metaslab group then we
+ * consider skipping it. We skip it only if we're allowed
+ * to "fast" gang, the physical size is larger than
+ * a gang block, and we're attempting to allocate from
+ * the primary metaslab.
+ */
+ if (mg->mg_alloc_failures > zfs_mg_alloc_failures &&
+ CAN_FASTGANG(flags) && psize > SPA_GANGBLOCKSIZE &&
+ activation_weight == METASLAB_WEIGHT_PRIMARY) {
+ spa_dbgmsg(spa, "%s: skipping metaslab group: "
+ "vdev %llu, txg %llu, mg %p, psize %llu, "
+ "asize %llu, failures %llu", spa_name(spa),
+ mg->mg_vd->vdev_id, txg, mg, psize, asize,
+ mg->mg_alloc_failures);
+ return (-1ULL);
+ }
+
mutex_enter(&msp->ms_lock);
/*
* another thread may have changed the weight while we
* were blocked on the metaslab lock.
*/
- if (msp->ms_weight < size) {
+ if (msp->ms_weight < asize || (was_active &&
+ !(msp->ms_weight & METASLAB_ACTIVE_MASK) &&
+ activation_weight == METASLAB_WEIGHT_PRIMARY)) {
mutex_exit(&msp->ms_lock);
continue;
}
continue;
}
- if ((offset = space_map_alloc(&msp->ms_map, size)) != -1ULL)
+ if ((offset = space_map_alloc(&msp->ms_map, asize)) != -1ULL)
break;
- metaslab_passivate(msp, size - 1);
+ atomic_inc_64(&mg->mg_alloc_failures);
+
+ metaslab_passivate(msp, space_map_maxsize(&msp->ms_map));
mutex_exit(&msp->ms_lock);
}
if (msp->ms_allocmap[txg & TXG_MASK].sm_space == 0)
vdev_dirty(mg->mg_vd, VDD_METASLAB, msp, txg);
- space_map_add(&msp->ms_allocmap[txg & TXG_MASK], offset, size);
+ space_map_add(&msp->ms_allocmap[txg & TXG_MASK], offset, asize);
mutex_exit(&msp->ms_lock);
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;
/*
* For testing, make some blocks above a certain size be gang blocks.
*/
- if (psize >= metaslab_gang_bang && (lbolt & 3) == 0)
+ if (psize >= metaslab_gang_bang && (ddi_get_lbolt() & 3) == 0)
return (ENOSPC);
/*
* Start at the rotor and loop through all mgs until we find something.
- * Note that there's no locking on mc_rotor or mc_allocated because
+ * Note that there's no locking on mc_rotor or mc_aliquot because
* nothing actually breaks if we miss a few updates -- we just won't
* allocate quite as evenly. It all balances out over time.
*
*/
if (hintdva) {
vd = vdev_lookup_top(spa, DVA_GET_VDEV(&hintdva[d]));
- if (flags & METASLAB_HINTBP_AVOID)
- mg = vd->vdev_mg->mg_next;
- else
+
+ /*
+ * It's possible the vdev we're using as the hint no
+ * longer exists (i.e. removed). Consult the rotor when
+ * all else fails.
+ */
+ if (vd != NULL) {
mg = vd->vdev_mg;
+
+ if (flags & METASLAB_HINTBP_AVOID &&
+ mg->mg_next != NULL)
+ mg = mg->mg_next;
+ } else {
+ mg = mc->mc_rotor;
+ }
} else if (d != 0) {
vd = vdev_lookup_top(spa, DVA_GET_VDEV(&dva[d - 1]));
mg = vd->vdev_mg->mg_next;
}
/*
- * If the hint put us into the wrong class, just follow the rotor.
+ * If the hint put us into the wrong metaslab class, or into a
+ * metaslab group that has been passivated, just follow the rotor.
*/
- if (mg->mg_class != mc)
+ if (mg->mg_class != mc || mg->mg_activation_count <= 0)
mg = mc->mc_rotor;
rotor = mg;
top:
all_zero = B_TRUE;
do {
+ ASSERT(mg->mg_activation_count == 1);
+
vd = mg->mg_vd;
+
/*
* Don't allocate from faulted devices.
*/
- if (!vdev_allocatable(vd))
+ if (zio_lock) {
+ spa_config_enter(spa, SCL_ZIO, FTAG, RW_READER);
+ allocatable = vdev_allocatable(vd);
+ spa_config_exit(spa, SCL_ZIO, FTAG);
+ } else {
+ allocatable = vdev_allocatable(vd);
+ }
+ if (!allocatable)
goto next;
+
/*
* Avoid writing single-copy data to a failing vdev
*/
asize = vdev_psize_to_asize(vd, psize);
ASSERT(P2PHASE(asize, 1ULL << vd->vdev_ashift) == 0);
- offset = metaslab_group_alloc(mg, asize, txg, distance, dva, d);
+ offset = metaslab_group_alloc(mg, psize, asize, txg, distance,
+ dva, d, flags);
if (offset != -1ULL) {
/*
* If we've just selected this metaslab group,
* over- or under-used relative to the pool,
* and set an allocation bias to even it out.
*/
- if (mc->mc_allocated == 0) {
+ if (mc->mc_aliquot == 0) {
vdev_stat_t *vs = &vd->vdev_stat;
- uint64_t alloc, space;
- int64_t vu, su;
+ int64_t vu, cu;
- alloc = spa_get_alloc(spa);
- space = spa_get_space(spa);
+ vu = (vs->vs_alloc * 100) / (vs->vs_space + 1);
+ cu = (mc->mc_alloc * 100) / (mc->mc_space + 1);
/*
- * Determine percent used in units of 0..1024.
- * (This is just to avoid floating point.)
+ * Calculate how much more or less we should
+ * try to allocate from this device during
+ * this iteration around the rotor.
+ * For example, if a device is 80% full
+ * and the pool is 20% full then we should
+ * reduce allocations by 60% on this device.
+ *
+ * mg_bias = (20 - 80) * 512K / 100 = -307K
+ *
+ * This reduces allocations by 307K for this
+ * iteration.
*/
- vu = (vs->vs_alloc << 10) / (vs->vs_space + 1);
- su = (alloc << 10) / (space + 1);
-
- /*
- * Bias by at most +/- 25% of the aliquot.
- */
- mg->mg_bias = ((su - vu) *
- (int64_t)mg->mg_aliquot) / (1024 * 4);
+ mg->mg_bias = ((cu - vu) *
+ (int64_t)mg->mg_aliquot) / 100;
}
- if (atomic_add_64_nv(&mc->mc_allocated, asize) >=
+ if (atomic_add_64_nv(&mc->mc_aliquot, asize) >=
mg->mg_aliquot + mg->mg_bias) {
mc->mc_rotor = mg->mg_next;
- mc->mc_allocated = 0;
+ mc->mc_aliquot = 0;
}
DVA_SET_VDEV(&dva[d], vd->vdev_id);
}
next:
mc->mc_rotor = mg->mg_next;
- mc->mc_allocated = 0;
+ mc->mc_aliquot = 0;
} while ((mg = mg->mg_next) != rotor);
if (!all_zero) {
goto top;
}
+ if (!allocatable && !zio_lock) {
+ dshift = 3;
+ zio_lock = B_TRUE;
+ goto top;
+ }
+
bzero(&dva[d], sizeof (dva_t));
return (ENOSPC);
uint64_t size = DVA_GET_ASIZE(dva);
vdev_t *vd;
metaslab_t *msp;
- int error;
+ int error = 0;
ASSERT(DVA_IS_VALID(dva));
mutex_enter(&msp->ms_lock);
- error = metaslab_activate(msp, METASLAB_WEIGHT_SECONDARY);
+ if ((txg != 0 && spa_writeable(spa)) || !msp->ms_map.sm_loaded)
+ error = metaslab_activate(msp, METASLAB_WEIGHT_SECONDARY);
+
+ if (error == 0 && !space_map_contains(&msp->ms_map, offset, size))
+ error = ENOENT;
+
if (error || txg == 0) { /* txg == 0 indicates dry run */
mutex_exit(&msp->ms_lock);
return (error);
space_map_claim(&msp->ms_map, offset, size);
- if (spa_mode & FWRITE) { /* don't dirty if we're zdb(1M) */
+ if (spa_writeable(spa)) { /* don't dirty if we're zdb(1M) */
if (msp->ms_allocmap[txg & TXG_MASK].sm_space == 0)
vdev_dirty(vd, VDD_METASLAB, msp, txg);
space_map_add(&msp->ms_allocmap[txg & TXG_MASK], offset, size);
{
dva_t *dva = bp->blk_dva;
dva_t *hintdva = hintbp->blk_dva;
- int error = 0;
+ int d, error = 0;
ASSERT(bp->blk_birth == 0);
+ ASSERT(BP_PHYSICAL_BIRTH(bp) == 0);
spa_config_enter(spa, SCL_ALLOC, FTAG, RW_READER);
ASSERT(BP_GET_NDVAS(bp) == 0);
ASSERT(hintbp == NULL || ndvas <= BP_GET_NDVAS(hintbp));
- for (int d = 0; d < ndvas; d++) {
+ for (d = 0; d < ndvas; d++) {
error = metaslab_alloc_dva(spa, mc, psize, dva, d, hintdva,
txg, flags);
if (error) {
spa_config_exit(spa, SCL_ALLOC, FTAG);
- bp->blk_birth = txg;
+ BP_SET_BIRTH(bp, txg, txg);
return (0);
}
metaslab_free(spa_t *spa, const blkptr_t *bp, uint64_t txg, boolean_t now)
{
const dva_t *dva = bp->blk_dva;
- int ndvas = BP_GET_NDVAS(bp);
+ int d, ndvas = BP_GET_NDVAS(bp);
ASSERT(!BP_IS_HOLE(bp));
- ASSERT(!now || bp->blk_birth >= spa->spa_syncing_txg);
+ ASSERT(!now || bp->blk_birth >= spa_syncing_txg(spa));
spa_config_enter(spa, SCL_FREE, FTAG, RW_READER);
- for (int d = 0; d < ndvas; d++)
+ for (d = 0; d < ndvas; d++)
metaslab_free_dva(spa, &dva[d], txg, now);
spa_config_exit(spa, SCL_FREE, FTAG);
{
const dva_t *dva = bp->blk_dva;
int ndvas = BP_GET_NDVAS(bp);
- int error = 0;
+ int d, error = 0;
ASSERT(!BP_IS_HOLE(bp));
spa_config_enter(spa, SCL_ALLOC, FTAG, RW_READER);
- for (int d = 0; d < ndvas; d++)
+ for (d = 0; d < ndvas; d++)
if ((error = metaslab_claim_dva(spa, &dva[d], txg)) != 0)
break;