diff options
| author | Max Reitz <mreitz@redhat.com> | 2014-08-18 22:07:31 +0200 |
|---|---|---|
| committer | Kevin Wolf <kwolf@redhat.com> | 2014-08-20 11:51:28 +0200 |
| commit | 440ba08aea3d841996efaf6a6b88426b0d59abf4 (patch) | |
| tree | 43d6edcbbb02d93890e70c2ae3025ce320db7a99 /block/qcow2.h | |
| parent | 18a7d0c56e1377f3d5fa1dc4d78a15dbab01cd83 (diff) | |
qcow2: Constant cache size in bytes
Specifying the metadata cache sizes in clusters results in less clusters
(and much less bytes) covered for small cluster sizes and vice versa.
Using a constant byte size reduces this difference, and makes it
possible to manually specify the cache size in an easily comprehensible
unit.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'block/qcow2.h')
| -rw-r--r-- | block/qcow2.h | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/block/qcow2.h b/block/qcow2.h index b49424b85e..671783defe 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -64,10 +64,16 @@ #define MIN_CLUSTER_BITS 9 #define MAX_CLUSTER_BITS 21 -#define L2_CACHE_SIZE 16 +#define MIN_L2_CACHE_SIZE 1 /* cluster */ /* Must be at least 4 to cover all cases of refcount table growth */ -#define REFCOUNT_CACHE_SIZE 4 +#define MIN_REFCOUNT_CACHE_SIZE 4 /* clusters */ + +#define DEFAULT_L2_CACHE_BYTE_SIZE 1048576 /* bytes */ + +/* The refblock cache needs only a fourth of the L2 cache size to cover as many + * clusters */ +#define DEFAULT_L2_REFCOUNT_SIZE_RATIO 4 #define DEFAULT_CLUSTER_SIZE 65536 |