diff options
| author | Mike Snitzer <snitzer@redhat.com> | 2013-08-16 10:54:19 -0400 |
|---|---|---|
| committer | Mike Snitzer <snitzer@redhat.com> | 2013-08-23 09:02:13 -0400 |
| commit | 054730446315d2a9a41f4232ebf1d5034244d054 (patch) | |
| tree | eefe6fe46fc3d389932bcac4988d9a253649f599 /Documentation/device-mapper/cache.txt | |
| parent | 66bb2644cac8b5cc1cc477959aa37dcfe6317a23 (diff) | |
dm cache: add data block size limits to code and Documentation
Place upper bound on the cache's data block size (1GB).
Inform users that the data block size can't be any arbitrary number,
i.e. its value must be between 32KB and 1GB. Also, it should be a
multiple of 32KB.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Diffstat (limited to 'Documentation/device-mapper/cache.txt')
| -rw-r--r-- | Documentation/device-mapper/cache.txt | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/Documentation/device-mapper/cache.txt b/Documentation/device-mapper/cache.txt index af99c458c841..33d45ee0b737 100644 --- a/Documentation/device-mapper/cache.txt +++ b/Documentation/device-mapper/cache.txt @@ -58,7 +58,8 @@ Fixed block size The origin is divided up into blocks of a fixed size. This block size is configurable when you first create the cache. Typically we've been -using block sizes of 256k - 1024k. +using block sizes of 256KB - 1024KB. The block size must be between 64 +(32KB) and 2097152 (1GB) and a multiple of 64 (32KB). Having a fixed block size simplifies the target a lot. But it is something of a compromise. For instance, a small part of a block may be |