Illumos #4101, #4102, #4103, #4105, #4106

4101 metaslab_debug should allow for fine-grained control
4102 space_maps should store more information about themselves
4103 space map object blocksize should be increased
4105 removing a mirrored log device results in a leaked object
4106 asynchronously load metaslab
Reviewed by: Matthew Ahrens <[email protected]>
Reviewed by: Adam Leventhal <[email protected]>
Reviewed by: Sebastien Roy <[email protected]>
Approved by: Garrett D'Amore <[email protected]>

Prior to this patch, space_maps were preferred solely based on the
amount of free space left in each. Unfortunately, this heuristic didn't
contain any information about the make-up of that free space, which
meant we could keep preferring and loading a highly fragmented space map
that wouldn't actually have enough contiguous space to satisfy the
allocation; then unloading that space_map and repeating the process.

This change modifies the space_map's to store additional information
about the contiguous space in the space_map, so that we can use this
information to make a better decision about which space_map to load.
This requires reallocating all space_map objects to increase their
bonus buffer size sizes enough to fit the new metadata.

The above feature can be enabled via a new feature flag introduced by
this change: com.delphix:spacemap_histogram

In addition to the above, this patch allows the space_map block size to
be increase. Currently the block size is set to be 4K in size, which has
certain implications including the following:

    * 4K sector devices will not see any compression benefit
    * large space_maps require more metadata on-disk
    * large space_maps require more time to load (typically random reads)

Now the space_map block size can adjust as needed up to the maximum size
set via the space_map_max_blksz variable.

A bug was fixed which resulted in potentially leaking an object when
removing a mirrored log device. The previous logic for vdev_remove() did
not deal with removing top-level vdevs that are interior vdevs (i.e.
mirror) correctly. The problem would occur when removing a mirrored log
device, and result in the DTL space map object being leaked; because
top-level vdevs don't have DTL space map objects associated with them.

References:
  https://www.illumos.org/issues/4101
  https://www.illumos.org/issues/4102
  https://www.illumos.org/issues/4103
  https://www.illumos.org/issues/4105
  https://www.illumos.org/issues/4106
  https://github.com/illumos/illumos-gate/commit/0713e23

Porting notes:

A handful of kmem_alloc() calls were converted to kmem_zalloc(). Also,
the KM_PUSHPAGE and TQ_PUSHPAGE flags were used as necessary.

Ported-by: Tim Chase <[email protected]>
Signed-off-by: Prakash Surya <[email protected]>
Signed-off-by: Brian Behlendorf <[email protected]>
Closes #2488

1 files changed, 14 insertions, 12 deletions

diff --git a/include/sys/vdev_impl.h b/include/sys/vdev_impl.h
index 703dd65da..16cf4d770 100644
--- a/include/sys/vdev_impl.h
+++ b/include/sys/vdev_impl.h
@@ -152,7 +152,6 @@ struct vdev {
 	vdev_t		*vdev_parent;	/* parent vdev			*/
 	vdev_t		**vdev_child;	/* array of children		*/
 	uint64_t	vdev_children;	/* number of children		*/
-	space_map_t	vdev_dtl[DTL_TYPES]; /* in-core dirty time logs	*/
 	vdev_stat_t	vdev_stat;	/* virtual device statistics	*/
 	boolean_t	vdev_expanding;	/* expand the vdev?		*/
 	boolean_t	vdev_reopening;	/* reopen in progress?		*/
@@ -174,19 +173,21 @@ struct vdev {
 	txg_node_t	vdev_txg_node;	/* per-txg dirty vdev linkage	*/
 	boolean_t	vdev_remove_wanted; /* async remove wanted?	*/
 	boolean_t	vdev_probe_wanted; /* async probe wanted?	*/
-	uint64_t	vdev_removing;	/* device is being removed?	*/
 	list_node_t	vdev_config_dirty_node; /* config dirty list	*/
 	list_node_t	vdev_state_dirty_node; /* state dirty list	*/
 	uint64_t	vdev_deflate_ratio; /* deflation ratio (x512)	*/
 	uint64_t	vdev_islog;	/* is an intent log device	*/
-	uint64_t	vdev_ishole;	/* is a hole in the namespace 	*/
+	uint64_t	vdev_removing;	/* device is being removed?	*/
+	boolean_t	vdev_ishole;	/* is a hole in the namespace 	*/
 
 	/*
 	 * Leaf vdev state.
 	 */
-	uint64_t	vdev_psize;	/* physical device capacity	*/
-	space_map_obj_t	vdev_dtl_smo;	/* dirty time log space map obj	*/
+	range_tree_t	*vdev_dtl[DTL_TYPES]; /* dirty time logs	*/
+	space_map_t	*vdev_dtl_sm;	/* dirty time log space map	*/
 	txg_node_t	vdev_dtl_node;	/* per-txg dirty DTL linkage	*/
+	uint64_t	vdev_dtl_object; /* DTL object			*/
+	uint64_t	vdev_psize;	/* physical device capacity	*/
 	uint64_t	vdev_wholedisk;	/* true if this is a whole disk */
 	uint64_t	vdev_offline;	/* persistent offline state	*/
 	uint64_t	vdev_faulted;	/* persistent faulted state	*/
@@ -200,18 +201,17 @@ struct vdev {
 	char		*vdev_fru;	/* physical FRU location	*/
 	uint64_t	vdev_not_present; /* not present during import	*/
 	uint64_t	vdev_unspare;	/* unspare when resilvering done */
-	hrtime_t	vdev_last_try;	/* last reopen time		*/
 	boolean_t	vdev_nowritecache; /* true if flushwritecache failed */
 	boolean_t	vdev_checkremove; /* temporary online test	*/
 	boolean_t	vdev_forcefault; /* force online fault		*/
 	boolean_t	vdev_splitting;	/* split or repair in progress  */
 	boolean_t	vdev_delayed_close; /* delayed device close?	*/
-	uint8_t		vdev_tmpoffline; /* device taken offline temporarily? */
-	uint8_t		vdev_detached;	/* device detached?		*/
-	uint8_t		vdev_cant_read;	/* vdev is failing all reads	*/
-	uint8_t		vdev_cant_write; /* vdev is failing all writes	*/
-	uint64_t	vdev_isspare;	/* was a hot spare		*/
-	uint64_t	vdev_isl2cache;	/* was a l2cache device		*/
+	boolean_t	vdev_tmpoffline; /* device taken offline temporarily? */
+	boolean_t	vdev_detached;	/* device detached?		*/
+	boolean_t	vdev_cant_read;	/* vdev is failing all reads	*/
+	boolean_t	vdev_cant_write; /* vdev is failing all writes	*/
+	boolean_t	vdev_isspare;	/* was a hot spare		*/
+	boolean_t	vdev_isl2cache;	/* was a l2cache device		*/
 	vdev_queue_t	vdev_queue;	/* I/O deadline schedule queue	*/
 	vdev_cache_t	vdev_cache;	/* physical block cache		*/
 	spa_aux_vdev_t	*vdev_aux;	/* for l2cache vdevs		*/
@@ -312,9 +312,11 @@ extern void vdev_remove_parent(vdev_t *cvd);
 extern void vdev_load_log_state(vdev_t *nvd, vdev_t *ovd);
 extern boolean_t vdev_log_state_valid(vdev_t *vd);
 extern void vdev_load(vdev_t *vd);
+extern int vdev_dtl_load(vdev_t *vd);
 extern void vdev_sync(vdev_t *vd, uint64_t txg);
 extern void vdev_sync_done(vdev_t *vd, uint64_t txg);
 extern void vdev_dirty(vdev_t *vd, int flags, void *arg, uint64_t txg);
+extern void vdev_dirty_leaves(vdev_t *vd, int flags, uint64_t txg);
 
 /*
  * Available vdev types.