diff options
| author | Joe Thornber <ejt@redhat.com> | 2021-04-13 11:03:45 +0100 |
|---|---|---|
| committer | Mike Snitzer <snitzer@redhat.com> | 2021-06-04 12:07:22 -0400 |
| commit | be500ed721a6ec8d49bf0814c277ce7162acee0e (patch) | |
| tree | b61c5518a38b187dd2ffd4a830ca64105e41fe2c /drivers/md/persistent-data/dm-btree.h | |
| parent | 5faafc77f7de69147d1e818026b9a0cbf036a7b2 (diff) | |
dm space maps: improve performance with inc/dec on ranges of blocks
When we break sharing on btree nodes we typically need to increment
the reference counts to every value held in the node. This can
cause a lot of repeated calls to the space maps. Fix this by changing
the interface to the space map inc/dec methods to take ranges of
adjacent blocks to be operated on.
For installations that are using a lot of snapshots this will reduce
cpu overhead of fundamental operations such as provisioning a new block,
or deleting a snapshot, by as much as 10 times.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Diffstat (limited to 'drivers/md/persistent-data/dm-btree.h')
| -rw-r--r-- | drivers/md/persistent-data/dm-btree.h | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/drivers/md/persistent-data/dm-btree.h b/drivers/md/persistent-data/dm-btree.h index 3dc5bb1a4748..d2ae5aa4d00b 100644 --- a/drivers/md/persistent-data/dm-btree.h +++ b/drivers/md/persistent-data/dm-btree.h @@ -51,21 +51,21 @@ struct dm_btree_value_type { */ /* - * The btree is making a duplicate of the value, for instance + * The btree is making a duplicate of a run of values, for instance * because previously-shared btree nodes have now diverged. * @value argument is the new copy that the copy function may modify. * (Probably it just wants to increment a reference count * somewhere.) This method is _not_ called for insertion of a new * value: It is assumed the ref count is already 1. */ - void (*inc)(void *context, const void *value); + void (*inc)(void *context, const void *value, unsigned count); /* - * This value is being deleted. The btree takes care of freeing + * These values are being deleted. The btree takes care of freeing * the memory pointed to by @value. Often the del function just - * needs to decrement a reference count somewhere. + * needs to decrement a reference counts somewhere. */ - void (*dec)(void *context, const void *value); + void (*dec)(void *context, const void *value, unsigned count); /* * A test for equality between two values. When a value is |