From fe0a797a6b42d9ad0ed063eaef705da1eb3c8147 Mon Sep 17 00:00:00 2001 From: Gabriel Date: Wed, 24 Apr 2013 19:51:02 +0200 Subject: bcache: clarify free/available/unused space Don't describe bcache_available_percent as free space but as non-writeback space. Describe priority_stats in more detail and point to that for total bcache occupation. Signed-off-by: Gabriel de Perthuis Signed-off-by: Kent Overstreet --- Documentation/bcache.txt | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) (limited to 'Documentation') diff --git a/Documentation/bcache.txt b/Documentation/bcache.txt index 77db8809bd96..b3a7e7d384f6 100644 --- a/Documentation/bcache.txt +++ b/Documentation/bcache.txt @@ -319,7 +319,10 @@ cache<0..n> Symlink to each of the cache devices comprising this cache set. cache_available_percent - Percentage of cache device free. + Percentage of cache device which doesn't contain dirty data, and could + potentially be used for writeback. This doesn't mean this space isn't used + for clean cached data; the unused statistic (in priority_stats) is typically + much lower. clear_stats Clears the statistics associated with this cache @@ -423,8 +426,11 @@ nbuckets Total buckets in this cache priority_stats - Statistics about how recently data in the cache has been accessed. This can - reveal your working set size. + Statistics about how recently data in the cache has been accessed. + This can reveal your working set size. Unused is the percentage of + the cache that doesn't contain any data. Metadata is bcache's + metadata overhead. Average is the average priority of cache buckets. + Next is a list of quantiles with the priority threshold of each. written Sum of all data that has been written to the cache; comparison with -- cgit v1.2.1