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| author | Alberto Garcia <berto@igalia.com> | 2015-08-04 15:14:40 +0300 |
|---|---|---|
| committer | Max Reitz <mreitz@redhat.com> | 2015-09-04 21:00:32 +0200 |
| commit | 279621c046ce57de0af9e3c00663b48d3a7835ae (patch) | |
| tree | e14d8ab78e7bfcddf42b763a120cc8d116d38430 /block/qcow2.h | |
| parent | 355ee2d0e8ca536a6278c9c763ddd2f136eace3f (diff) | |
| download | qemu-279621c046ce57de0af9e3c00663b48d3a7835ae.tar.gz | |
qcow2: add option to clean unused cache entries after some time
This adds a new 'cache-clean-interval' option that cleans all qcow2
cache entries that haven't been used in a certain interval, given in
seconds.
This allows setting a large L2 cache size so it can handle scenarios
with lots of I/O and at the same time use little memory during periods
of inactivity.
This feature currently relies on MADV_DONTNEED to free that memory, so
it is not useful in systems that don't follow that behavior.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: a70d12da60433df9360ada648b3f34b8f6f354ce.1438690126.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Diffstat (limited to 'block/qcow2.h')
| -rw-r--r-- | block/qcow2.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/block/qcow2.h b/block/qcow2.h index 72e132838a..71dafd6dc9 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -96,6 +96,7 @@ #define QCOW2_OPT_CACHE_SIZE "cache-size" #define QCOW2_OPT_L2_CACHE_SIZE "l2-cache-size" #define QCOW2_OPT_REFCOUNT_CACHE_SIZE "refcount-cache-size" +#define QCOW2_OPT_CACHE_CLEAN_INTERVAL "cache-clean-interval" typedef struct QCowHeader { uint32_t magic; @@ -239,6 +240,8 @@ typedef struct BDRVQcowState { Qcow2Cache* l2_table_cache; Qcow2Cache* refcount_block_cache; + QEMUTimer *cache_clean_timer; + unsigned cache_clean_interval; uint8_t *cluster_cache; uint8_t *cluster_data; @@ -581,6 +584,7 @@ int qcow2_cache_set_dependency(BlockDriverState *bs, Qcow2Cache *c, Qcow2Cache *dependency); void qcow2_cache_depends_on_flush(Qcow2Cache *c); +void qcow2_cache_clean_unused(BlockDriverState *bs, Qcow2Cache *c); int qcow2_cache_empty(BlockDriverState *bs, Qcow2Cache *c); int qcow2_cache_get(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset, |