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authorLinus Torvalds <torvalds@linux-foundation.org>2013-11-14 03:35:48 (GMT)
committerLinus Torvalds <torvalds@linux-foundation.org>2013-11-14 03:35:48 (GMT)
commit7f2dc5c4bcbff035b0d03f7aa78a182664b21e47 (patch)
treef4a5ff92305fbf70f1cba3a1ced0f492b27aab74 /Documentation/device-mapper/cache-policies.txt
parent82cb6acea4d10fa4080612c58deb63993f558e5a (diff)
parent7b6b2bc98c0303b7f043ad5b35906f833e56308d (diff)
downloadlinux-fsl-qoriq-7f2dc5c4bcbff035b0d03f7aa78a182664b21e47.tar.xz
Merge tag 'dm-3.13-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper changes from Mike Snitzer: "A set of device-mapper changes for 3.13. Improve reliability of buffer allocations for dm messages with a small number of arguments, a couple path group initialization fixes for dm multipath, a fix for resizing a dm array, various fixes and optimizations for dm cache, a fix for device mapper's Kconfig menu indentation. Features added include: - dm crypt support for activating legacy CBC TrueCrypt containers (useful for forensics of these old TCRYPT containers) - reduced dm-cache memory requirements for each block in the cache - basic support for shrinking a dm-cache's cache (fast) device - most notably, dm-cache support for managing cache coherency when deploying dm-cache with sophisticated origin volumes (that support hardware snapshots and/or clustering): these changes come in the form of a new passthrough operation mode and a cache block invalidation interface" * tag 'dm-3.13-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (32 commits) dm cache: resolve small nits and improve Documentation dm cache: add cache block invalidation support dm cache: add remove_cblock method to policy interface dm cache policy mq: reduce memory requirements dm cache metadata: check the metadata version when reading the superblock dm cache: add passthrough mode dm cache: cache shrinking support dm cache: promotion optimisation for writes dm cache: be much more aggressive about promoting writes to discarded blocks dm cache policy mq: implement writeback_work() and mq_{set,clear}_dirty() dm cache: optimize commit_if_needed dm space map disk: optimise sm_disk_dec_block MAINTAINERS: add reference to device-mapper's linux-dm.git tree dm: fix Kconfig menu indentation dm: allow remove to be deferred dm table: print error on preresume failure dm crypt: add TCW IV mode for old CBC TCRYPT containers dm crypt: properly handle extra key string in initialization dm cache: log error message if dm_kcopyd_copy() fails dm cache: use cell_defer() boolean argument consistently ...
Diffstat (limited to 'Documentation/device-mapper/cache-policies.txt')
-rw-r--r--Documentation/device-mapper/cache-policies.txt6
1 files changed, 4 insertions, 2 deletions
diff --git a/Documentation/device-mapper/cache-policies.txt b/Documentation/device-mapper/cache-policies.txt
index d7c440b..df52a84 100644
--- a/Documentation/device-mapper/cache-policies.txt
+++ b/Documentation/device-mapper/cache-policies.txt
@@ -30,8 +30,10 @@ multiqueue
This policy is the default.
-The multiqueue policy has two sets of 16 queues: one set for entries
-waiting for the cache and another one for those in the cache.
+The multiqueue policy has three sets of 16 queues: one set for entries
+waiting for the cache and another two for those in the cache (a set for
+clean entries and a set for dirty entries).
+
Cache entries in the queues are aged based on logical time. Entry into
the cache is based on variable thresholds and queue selection is based
on hit count on entry. The policy aims to take different cache miss