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NEX-9673 Add capability to replicate cloned datasets relative to origin
Reviewed by: Alex Deiter <alex.deiter@nexenta.com>
Reviewed by: Sanjay Nadkarni <sanjay.nadkarni@nexenta.com>
NEX-5085 implement async delete for large files
Reviewed by: Saso Kiselkov <saso.kiselkov@nexenta.com>
Reviewed by: Roman Strashkin <roman.strashkin@nexenta.com>
Reviewed by: Sanjay Nadkarni <sanjay.nadkarni@nexenta.com>
Revert "NEX-5085 implement async delete for large files"
This reverts commit 65aa8f42d93fcbd6e0efb3d4883170a20d760611.
Fails regression testing of the zfs test mirror_stress_004.
NEX-5085 implement async delete for large files
Reviewed by: Sanjay Nadkarni <sanjay.nadkarni@nexenta.com>
Reviewed by: Roman Strashkin <roman.strashkin@nexenta.com>
Reviewed by: Kirill Davydychev <kirill.davydychev@nexenta.com>
NEX-7479 Autosnap may dispatch duplicated sync-tasks
Reviewed by: Alex Deiter <alex.deiter@nexenta.com>
Reviewed by: Sanjay Nadkarni <sanjay.nadkarni@nexent.com>
NEX-7543 backout async delete (NEX-5085 and NEX-6151)
Reviewed by: Roman Strashkin <roman.strashkin@nexenta.com>
Reviewed by: Yuri Pankov <yuri.pankov@nexenta.com>
Reviewed by: Sanjay Nadkarni <sanjay.nadkarni@nexenta.com>
NEX-5795 Rename 'wrc' as 'wbc' in the source and in the tech docs
Reviewed by: Alex Aizman <alex.aizman@nexenta.com>
Reviewed by: Sanjay Nadkarni <sanjay.nadkarni@nexenta.com>
Reviewed by: Alek Pinchuk <alek.pinchuk@nexenta.com>
NEX-5078 Want ability to see progress of freeing data and how much is left to free after large file delete patch
Reviewed by: Saso Kiselkov <saso.kiselkov@nexenta.com>
Reviewed by: Sanjay Nadkarni <sanjay.nadkarni@nexenta.com>
NEX-5085 implement async delete for large files
Reviewed by: Marcel Telka <marcel.telka@nexenta.com>
Reviewed by: Saso Kiselkov <saso.kiselkov@nexenta.com>
NEX-5024 Slow performance with a single large file delete
Reviewed by: Saso Kiselkov <saso.kiselkov@nexenta.com>
Reviewed by: Sanjay Nadkarni <sanjay.nadkarni@nexenta.com>
NEX-4830 writecache=off leaks data on special vdev (the data will never migrate)
Reviewed by: Alex Aizman <alex.aizman@nexenta.com>
Reviewed by: Saso Kiselkov <saso.kiselkov@nexenta.com>
5981 Deadlock in dmu_objset_find_dp
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Approved by: Robert Mustacchi <rm@joyent.com>
5269 zpool import slow
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george@delphix.com>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Approved by: Dan McDonald <danmcd@omniti.com>
NEX-4476 WRC: Allow to use write back cache per tree of datasets
Reviewed by: Alek Pinchuk <alek.pinchuk@nexenta.com>
Reviewed by: Alex Aizman <alex.aizman@nexenta.com>
Revert "NEX-4476 WRC: Allow to use write back cache per tree of datasets"
This reverts commit fe97b74444278a6f36fec93179133641296312da.
NEX-4476 WRC: Allow to use write back cache per tree of datasets
Reviewed by: Alek Pinchuk <alek.pinchuk@nexenta.com>
Reviewed by: Alex Aizman <alex.aizman@nexenta.com>
NEX-3964 It should not be allowed to rename a snapshot that its new name is matched to the prefix of in-kernel autosnapshots
Reviewed by: Alek Pinchuk <alek.pinchuk@nexenta.com>
Reviewed by: Josef 'Jeff' Sipek <josef.sipek@nexenta.com>
NEX-3485 Deferred deletes causing loss of service for NFS clients on cluster failover
Reviewed by: Marcel Telka <marcel.telka@nexenta.com>
Reviewed by: Saso Kiselkov <saso.kiselkov@nexenta.com>
NEX-3558 KRRP Integration
NEX-3079 port illumos ARC improvements
Fixup merge results
re #13253 rb4328 ssh: openssl version checking needs updating
re #11441 rb4292 panic in apic_record_rdt_entry on VMware hardware version 9
re #12619, rb4287 Deadlocked zfs txg processing in dsl_sync_task_group_sync()
re #12585 rb4049 ZFS++ work port - refactoring to improve separation of open/closed code, bug fixes, performance improvements - open code
Bug 11205: add missing libzfs_closed_stubs.c to fix opensource-only build.
ZFS plus work: special vdevs, cos, cos/vdev properties
        
*** 25,43 ****
--- 25,46 ----
   * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
   * Copyright (c) 2014 Integros [integros.com]
   * Copyright 2016 Nexenta Systems, Inc. All rights reserved.
   */
  
+ #include <sys/autosnap.h>
  #include <sys/dsl_pool.h>
  #include <sys/dsl_dataset.h>
  #include <sys/dsl_prop.h>
  #include <sys/dsl_dir.h>
  #include <sys/dsl_synctask.h>
+ #include <sys/dsl_dataset.h>
  #include <sys/dsl_scan.h>
  #include <sys/dnode.h>
  #include <sys/dmu_tx.h>
  #include <sys/dmu_objset.h>
+ #include <sys/dmu_traverse.h>
  #include <sys/arc.h>
  #include <sys/zap.h>
  #include <sys/zio.h>
  #include <sys/zfs_context.h>
  #include <sys/fs/zfs.h>
*** 47,56 ****
--- 50,62 ----
  #include <sys/bptree.h>
  #include <sys/zfeature.h>
  #include <sys/zil_impl.h>
  #include <sys/dsl_userhold.h>
  
+ #include <sys/wbc.h>
+ #include <sys/time.h>
+ 
  /*
   * ZFS Write Throttle
   * ------------------
   *
   * ZFS must limit the rate of incoming writes to the rate at which it is able
*** 160,169 ****
--- 166,181 ----
   */
  int zfs_zil_clean_taskq_nthr_pct = 100;
  int zfs_zil_clean_taskq_minalloc = 1024;
  int zfs_zil_clean_taskq_maxalloc = 1024 * 1024;
  
+ /*
+  * Tunable to control max number of tasks available for processing of
+  * deferred deletes.
+  */
+ int zfs_vn_rele_max_tasks = 256;
+ 
  int
  dsl_pool_open_special_dir(dsl_pool_t *dp, const char *name, dsl_dir_t **ddp)
  {
          uint64_t obj;
          int err;
*** 185,194 ****
--- 197,209 ----
  
          dp = kmem_zalloc(sizeof (dsl_pool_t), KM_SLEEP);
          dp->dp_spa = spa;
          dp->dp_meta_rootbp = *bp;
          rrw_init(&dp->dp_config_rwlock, B_TRUE);
+ 
+         dp->dp_sync_history[0] = dp->dp_sync_history[1] = 0;
+ 
          txg_init(dp, txg);
  
          txg_list_create(&dp->dp_dirty_datasets, spa,
              offsetof(dsl_dataset_t, ds_dirty_link));
          txg_list_create(&dp->dp_dirty_zilogs, spa,
*** 209,220 ****
              TASKQ_PREPOPULATE | TASKQ_THREADS_CPU_PCT);
  
          mutex_init(&dp->dp_lock, NULL, MUTEX_DEFAULT, NULL);
          cv_init(&dp->dp_spaceavail_cv, NULL, CV_DEFAULT, NULL);
  
!         dp->dp_vnrele_taskq = taskq_create("zfs_vn_rele_taskq", 1, minclsyspri,
!             1, 4, 0);
  
          return (dp);
  }
  
  int
--- 224,236 ----
              TASKQ_PREPOPULATE | TASKQ_THREADS_CPU_PCT);
  
          mutex_init(&dp->dp_lock, NULL, MUTEX_DEFAULT, NULL);
          cv_init(&dp->dp_spaceavail_cv, NULL, CV_DEFAULT, NULL);
  
!         dp->dp_vnrele_taskq = taskq_create("zfs_vn_rele_taskq",
!             zfs_vn_rele_max_tasks, minclsyspri,
!             1, zfs_vn_rele_max_tasks, TASKQ_DYNAMIC);
  
          return (dp);
  }
  
  int
*** 286,315 ****
                          goto out;
                  VERIFY0(bpobj_open(&dp->dp_free_bpobj,
                      dp->dp_meta_objset, obj));
          }
  
-         if (spa_feature_is_active(dp->dp_spa, SPA_FEATURE_OBSOLETE_COUNTS)) {
-                 err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
-                     DMU_POOL_OBSOLETE_BPOBJ, sizeof (uint64_t), 1, &obj);
-                 if (err == 0) {
-                         VERIFY0(bpobj_open(&dp->dp_obsolete_bpobj,
-                             dp->dp_meta_objset, obj));
-                 } else if (err == ENOENT) {
                          /*
!                          * We might not have created the remap bpobj yet.
                           */
-                         err = 0;
-                 } else {
-                         goto out;
-                 }
-         }
- 
-         /*
-          * Note: errors ignored, because the these special dirs, used for
-          * space accounting, are only created on demand.
-          */
          (void) dsl_pool_open_special_dir(dp, LEAK_DIR_NAME,
              &dp->dp_leak_dir);
  
          if (spa_feature_is_active(dp->dp_spa, SPA_FEATURE_ASYNC_DESTROY)) {
                  err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
--- 302,315 ----
                          goto out;
                  VERIFY0(bpobj_open(&dp->dp_free_bpobj,
                      dp->dp_meta_objset, obj));
          }
  
          /*
!          * Note: errors ignored, because the leak dir will not exist if we
!          * have not encountered a leak yet.
           */
          (void) dsl_pool_open_special_dir(dp, LEAK_DIR_NAME,
              &dp->dp_leak_dir);
  
          if (spa_feature_is_active(dp->dp_spa, SPA_FEATURE_ASYNC_DESTROY)) {
                  err = zap_lookup(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
*** 350,375 ****
           *
           * Since we held the origin_snap from "syncing" context (which
           * includes pool-opening context), it actually only got a "ref"
           * and not a hold, so just drop that here.
           */
!         if (dp->dp_origin_snap != NULL)
                  dsl_dataset_rele(dp->dp_origin_snap, dp);
!         if (dp->dp_mos_dir != NULL)
                  dsl_dir_rele(dp->dp_mos_dir, dp);
!         if (dp->dp_free_dir != NULL)
                  dsl_dir_rele(dp->dp_free_dir, dp);
!         if (dp->dp_leak_dir != NULL)
                  dsl_dir_rele(dp->dp_leak_dir, dp);
!         if (dp->dp_root_dir != NULL)
                  dsl_dir_rele(dp->dp_root_dir, dp);
  
          bpobj_close(&dp->dp_free_bpobj);
-         bpobj_close(&dp->dp_obsolete_bpobj);
  
          /* undo the dmu_objset_open_impl(mos) from dsl_pool_open() */
!         if (dp->dp_meta_objset != NULL)
                  dmu_objset_evict(dp->dp_meta_objset);
  
          txg_list_destroy(&dp->dp_dirty_datasets);
          txg_list_destroy(&dp->dp_dirty_zilogs);
          txg_list_destroy(&dp->dp_sync_tasks);
--- 350,374 ----
           *
           * Since we held the origin_snap from "syncing" context (which
           * includes pool-opening context), it actually only got a "ref"
           * and not a hold, so just drop that here.
           */
!         if (dp->dp_origin_snap)
                  dsl_dataset_rele(dp->dp_origin_snap, dp);
!         if (dp->dp_mos_dir)
                  dsl_dir_rele(dp->dp_mos_dir, dp);
!         if (dp->dp_free_dir)
                  dsl_dir_rele(dp->dp_free_dir, dp);
!         if (dp->dp_leak_dir)
                  dsl_dir_rele(dp->dp_leak_dir, dp);
!         if (dp->dp_root_dir)
                  dsl_dir_rele(dp->dp_root_dir, dp);
  
          bpobj_close(&dp->dp_free_bpobj);
  
          /* undo the dmu_objset_open_impl(mos) from dsl_pool_open() */
!         if (dp->dp_meta_objset)
                  dmu_objset_evict(dp->dp_meta_objset);
  
          txg_list_destroy(&dp->dp_dirty_datasets);
          txg_list_destroy(&dp->dp_dirty_zilogs);
          txg_list_destroy(&dp->dp_sync_tasks);
*** 382,434 ****
           * We can't set retry to TRUE since we're explicitly specifying
           * a spa to flush. This is good enough; any missed buffers for
           * this spa won't cause trouble, and they'll eventually fall
           * out of the ARC just like any other unused buffer.
           */
!         arc_flush(dp->dp_spa, FALSE);
! 
          txg_fini(dp);
          dsl_scan_fini(dp);
          dmu_buf_user_evict_wait();
  
          rrw_destroy(&dp->dp_config_rwlock);
          mutex_destroy(&dp->dp_lock);
          taskq_destroy(dp->dp_vnrele_taskq);
!         if (dp->dp_blkstats != NULL)
                  kmem_free(dp->dp_blkstats, sizeof (zfs_all_blkstats_t));
          kmem_free(dp, sizeof (dsl_pool_t));
  }
  
- void
- dsl_pool_create_obsolete_bpobj(dsl_pool_t *dp, dmu_tx_t *tx)
- {
-         uint64_t obj;
-         /*
-          * Currently, we only create the obsolete_bpobj where there are
-          * indirect vdevs with referenced mappings.
-          */
-         ASSERT(spa_feature_is_active(dp->dp_spa, SPA_FEATURE_DEVICE_REMOVAL));
-         /* create and open the obsolete_bpobj */
-         obj = bpobj_alloc(dp->dp_meta_objset, SPA_OLD_MAXBLOCKSIZE, tx);
-         VERIFY0(bpobj_open(&dp->dp_obsolete_bpobj, dp->dp_meta_objset, obj));
-         VERIFY0(zap_add(dp->dp_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
-             DMU_POOL_OBSOLETE_BPOBJ, sizeof (uint64_t), 1, &obj, tx));
-         spa_feature_incr(dp->dp_spa, SPA_FEATURE_OBSOLETE_COUNTS, tx);
- }
- 
- void
- dsl_pool_destroy_obsolete_bpobj(dsl_pool_t *dp, dmu_tx_t *tx)
- {
-         spa_feature_decr(dp->dp_spa, SPA_FEATURE_OBSOLETE_COUNTS, tx);
-         VERIFY0(zap_remove(dp->dp_meta_objset,
-             DMU_POOL_DIRECTORY_OBJECT,
-             DMU_POOL_OBSOLETE_BPOBJ, tx));
-         bpobj_free(dp->dp_meta_objset,
-             dp->dp_obsolete_bpobj.bpo_object, tx);
-         bpobj_close(&dp->dp_obsolete_bpobj);
- }
- 
  dsl_pool_t *
  dsl_pool_create(spa_t *spa, nvlist_t *zplprops, uint64_t txg)
  {
          int err;
          dsl_pool_t *dp = dsl_pool_open_impl(spa, txg);
--- 381,403 ----
           * We can't set retry to TRUE since we're explicitly specifying
           * a spa to flush. This is good enough; any missed buffers for
           * this spa won't cause trouble, and they'll eventually fall
           * out of the ARC just like any other unused buffer.
           */
!         arc_flush(dp->dp_spa, B_FALSE);
          txg_fini(dp);
          dsl_scan_fini(dp);
          dmu_buf_user_evict_wait();
  
          rrw_destroy(&dp->dp_config_rwlock);
          mutex_destroy(&dp->dp_lock);
          taskq_destroy(dp->dp_vnrele_taskq);
!         if (dp->dp_blkstats)
                  kmem_free(dp->dp_blkstats, sizeof (zfs_all_blkstats_t));
          kmem_free(dp, sizeof (dsl_pool_t));
  }
  
  dsl_pool_t *
  dsl_pool_create(spa_t *spa, nvlist_t *zplprops, uint64_t txg)
  {
          int err;
          dsl_pool_t *dp = dsl_pool_open_impl(spa, txg);
*** 551,584 ****
--- 520,695 ----
          zio_t *zio;
          dmu_tx_t *tx;
          dsl_dir_t *dd;
          dsl_dataset_t *ds;
          objset_t *mos = dp->dp_meta_objset;
+         spa_t *spa = dp->dp_spa;
          list_t synced_datasets;
+         dsl_sync_task_t *iter;
+         boolean_t wbc_skip_txg = B_FALSE;
+         boolean_t sync_ops = B_FALSE;
+         boolean_t user_snap = B_FALSE;
+         zfs_autosnap_t *autosnap = spa_get_autosnap(spa);
+         boolean_t autosnap_initialized = autosnap->initialized;
+         char snap[ZFS_MAX_DATASET_NAME_LEN];
  
+         /* check if there are  ny sync ops in the txg */
+         if (txg_list_head(&dp->dp_sync_tasks, txg) != NULL)
+                 sync_ops = B_TRUE;
+ 
+         /* check if there are user snaps in the txg */
+         for (iter = txg_list_head(&dp->dp_sync_tasks, txg);
+             iter != NULL;
+             iter = txg_list_next(&dp->dp_sync_tasks, iter, txg)) {
+                 if (iter->dst_syncfunc == dsl_dataset_snapshot_sync) {
+                         user_snap = B_TRUE;
+                         break;
+                 }
+         }
+ 
+ 
          list_create(&synced_datasets, sizeof (dsl_dataset_t),
              offsetof(dsl_dataset_t, ds_synced_link));
  
          tx = dmu_tx_create_assigned(dp, txg);
  
+         (void) sprintf(snap, "%s%llu", AUTOSNAP_PREFIX,
+             (unsigned long long int) txg);
+ 
+         if (autosnap_initialized && spa->spa_sync_pass == 1) {
+                 autosnap_zone_t *azone;
+ 
+                 rrw_enter(&dp->dp_config_rwlock, RW_READER, FTAG);
+                 mutex_enter(&autosnap->autosnap_lock);
+ 
                  /*
+                  * WBC: the mechanism to ensure all WBC-ed dirty datasets
+                  * are synchronously auto-snapshotted
+                  * within (or by) the same TXG sync
+                  * The "synchronicity" of the rightmost boundary of the WBC
+                  * window is important to avoid used-space leakages
+                  * on special vdev.
+                  * Note that we skip here the WBC-ed datasets that are
+                  * already fully migrated and don't have data on special
+                  */
+ 
+                 for (ds = txg_list_head(&dp->dp_dirty_datasets, txg);
+                     ds != NULL;
+                     ds = txg_list_next(&dp->dp_dirty_datasets, ds, txg)) {
+                         char ds_name[ZFS_MAX_DATASET_NAME_LEN];
+                         boolean_t wbc_azone;
+ 
+                         dsl_dataset_name(ds, ds_name);
+ 
+                         azone = autosnap_find_zone(autosnap, ds_name, B_TRUE);
+                         if (azone == NULL)
+                                 continue;
+ 
+                         if ((azone->flags & AUTOSNAP_CREATOR) == 0)
+                                 continue;
+ 
+                         if (azone->created)
+                                 continue;
+ 
+                         azone->delayed = B_TRUE;
+                         azone->dirty = B_TRUE;
+                         wbc_azone = (azone->flags & AUTOSNAP_WBC) != 0;
+ 
+                         if (autosnap_confirm_snap(azone, txg)) {
+                                 if (!wbc_azone && !user_snap && !sync_ops) {
+                                         autosnap_create_snapshot(azone,
+                                             snap, dp, txg, tx);
+                                 }
+                         } else if (wbc_azone) {
+                                 wbc_skip_txg = B_TRUE;
+                         }
+                 }
+ 
+                 azone = list_head(&autosnap->autosnap_zones);
+                 while (azone != NULL) {
+                         boolean_t wbc_azone =
+                             ((azone->flags & AUTOSNAP_WBC) != 0);
+ 
+                         if (user_snap) {
+                                 azone->delayed = B_TRUE;
+                         } else if (!azone->dirty && azone->delayed) {
+                                 if (autosnap_confirm_snap(azone, txg)) {
+                                         if (!wbc_azone && !user_snap &&
+                                             !sync_ops) {
+                                                 autosnap_create_snapshot(azone,
+                                                     snap, dp, txg, tx);
+                                         }
+                                 } else if (wbc_azone) {
+                                         wbc_skip_txg = B_TRUE;
+                                 }
+                         }
+ 
+                         azone = list_next(&autosnap->autosnap_zones, azone);
+                 }
+ 
+                 mutex_exit(&autosnap->autosnap_lock);
+                 rrw_exit(&dp->dp_config_rwlock, FTAG);
+         }
+ 
+ 
+         /*
           * Write out all dirty blocks of dirty datasets.
           */
          zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED);
          while ((ds = txg_list_remove(&dp->dp_dirty_datasets, txg)) != NULL) {
+ 
                  /*
                   * We must not sync any non-MOS datasets twice, because
                   * we may have taken a snapshot of them.  However, we
                   * may sync newly-created datasets on pass 2.
                   */
                  ASSERT(!list_link_active(&ds->ds_synced_link));
                  list_insert_tail(&synced_datasets, ds);
                  dsl_dataset_sync(ds, zio, tx);
          }
+ 
          VERIFY0(zio_wait(zio));
  
+         if (autosnap_initialized && spa->spa_sync_pass == 1 &&
+             !user_snap) {
+                 autosnap_zone_t *azone;
+ 
+                 rrw_enter(&dp->dp_config_rwlock, RW_READER, FTAG);
+                 mutex_enter(&autosnap->autosnap_lock);
+ 
                  /*
+                  * At this stage we are walking over all delayed zones
+                  * to create autosnaps
+                  */
+ 
+                 azone = list_head(&autosnap->autosnap_zones);
+                 while (azone != NULL) {
+                         boolean_t skip_zone =
+                             ((azone->flags & AUTOSNAP_CREATOR) == 0);
+ 
+                         if (azone->delayed && !skip_zone) {
+                                 boolean_t wbc_azone =
+                                     ((azone->flags & AUTOSNAP_WBC) != 0);
+ 
+                                 if ((!wbc_azone || !wbc_skip_txg) &&
+                                     autosnap_confirm_snap(azone, txg)) {
+                                         autosnap_create_snapshot(azone,
+                                             snap, dp, txg, tx);
+                                 }
+                         }
+ 
+                         if (skip_zone)
+                                 azone->delayed = B_FALSE;
+ 
+                         azone = list_next(&autosnap->autosnap_zones, azone);
+                 }
+ 
+                 mutex_exit(&autosnap->autosnap_lock);
+                 rrw_exit(&dp->dp_config_rwlock, FTAG);
+         }
+ 
+         /*
           * We have written all of the accounted dirty data, so our
           * dp_space_towrite should now be zero.  However, some seldom-used
           * code paths do not adhere to this (e.g. dbuf_undirty(), also
           * rounding error in dbuf_write_physdone).
           * Shore up the accounting of any dirtied space now.
*** 590,599 ****
--- 701,712 ----
           * we're done syncing user data
           */
          mutex_enter(&dp->dp_lock);
          ASSERT(spa_sync_pass(dp->dp_spa) == 1 ||
              dp->dp_long_free_dirty_pertxg[txg & TXG_MASK] == 0);
+         dp->dp_long_freeing_total -=
+             dp->dp_long_free_dirty_pertxg[txg & TXG_MASK];
          dp->dp_long_free_dirty_pertxg[txg & TXG_MASK] = 0;
          mutex_exit(&dp->dp_lock);
  
          /*
           * After the data blocks have been written (ensured by the zio_wait()
*** 612,621 ****
--- 725,735 ----
           * userspace updates.  This must be done before we process the
           * sync tasks, so that any snapshots will have the correct
           * user accounting information (and we won't get confused
           * about which blocks are part of the snapshot).
           */
+ 
          zio = zio_root(dp->dp_spa, NULL, NULL, ZIO_FLAG_MUSTSUCCEED);
          while ((ds = txg_list_remove(&dp->dp_dirty_datasets, txg)) != NULL) {
                  ASSERT(list_link_active(&ds->ds_synced_link));
                  dmu_buf_rele(ds->ds_dbuf, ds);
                  dsl_dataset_sync(ds, zio, tx);
*** 663,672 ****
--- 777,787 ----
           * Therefore, we want to sync the MOS (thus syncing the dd_dbuf
           * and clearing the hold on it) before we process the sync_tasks.
           * The MOS data dirtied by the sync_tasks will be synced on the next
           * pass.
           */
+ 
          if (!txg_list_empty(&dp->dp_sync_tasks, txg)) {
                  dsl_sync_task_t *dst;
                  /*
                   * No more sync tasks should have been added while we
                   * were syncing.
*** 674,683 ****
--- 789,803 ----
                  ASSERT3U(spa_sync_pass(dp->dp_spa), ==, 1);
                  while ((dst = txg_list_remove(&dp->dp_sync_tasks, txg)) != NULL)
                          dsl_sync_task_sync(dst, tx);
          }
  
+         if (spa_feature_is_active(spa, SPA_FEATURE_WBC)) {
+                 wbc_trigger_wbcthread(dp->dp_spa,
+                     ((dp->dp_sync_history[0] + dp->dp_sync_history[1]) / 2));
+         }
+ 
          dmu_tx_commit(tx);
  
          DTRACE_PROBE2(dsl_pool_sync__done, dsl_pool_t *dp, dp, uint64_t, txg);
  }
  
*** 737,751 ****
  {
          uint64_t delay_min_bytes =
              zfs_dirty_data_max * zfs_delay_min_dirty_percent / 100;
          boolean_t rv;
  
-         mutex_enter(&dp->dp_lock);
          if (dp->dp_dirty_total > zfs_dirty_data_sync)
                  txg_kick(dp);
          rv = (dp->dp_dirty_total > delay_min_bytes);
!         mutex_exit(&dp->dp_lock);
          return (rv);
  }
  
  void
  dsl_pool_dirty_space(dsl_pool_t *dp, int64_t space, dmu_tx_t *tx)
--- 857,870 ----
  {
          uint64_t delay_min_bytes =
              zfs_dirty_data_max * zfs_delay_min_dirty_percent / 100;
          boolean_t rv;
  
          if (dp->dp_dirty_total > zfs_dirty_data_sync)
                  txg_kick(dp);
          rv = (dp->dp_dirty_total > delay_min_bytes);
! 
          return (rv);
  }
  
  void
  dsl_pool_dirty_space(dsl_pool_t *dp, int64_t space, dmu_tx_t *tx)