OptimumCache functionality is explained in previous post . Let break down it’s stats, to check cache use statistics run:
csums – number of marked files (control sums) in OptimumCache, 63.7% – their percentage from total files count in Linux kernel cache;
fetched – total files count in Linux kernel cache;
uncached – number of files not in OptimumCache;
cached – number of files in OptimumCache (with percentage);
de-duplication coefficient – percentage of de-duplicated file (share the same csum) in optimum cache.
csums min-max size filtered out – number of csumed inodes, filtered out by size criteria.
by min size – filtered out inodes, which size is less MINSIZE (see config).
by max size – filtered out inodes, which size is greater MAXSIZE (see config).
out range – filtered out inodes by any size criteria.
in range – not filtered out inodes. Only these inodes used for calculation of the de-duplication coefficient.
Higher value of de-duplication coefficient means bigger number of similar files and better performance.
Find ‘optimumcache stat –verbose’ breakdown explained in details here.
Note: On live systems it is unlikely possible to reach percentage lower than 25% due to different files/CMS used, number of content uploaded by customers, number of emails in mailboxes, etc.
Find all the necessery information on OptimumCache here http://docs.cloudlinux.com/index.html?optimumcache.html
Also, we are interested in building OptimumCache performance statistic from a live servers. If you have something to say about it or you did some tests, please let us know via submitting a ticket: https://helpdesk.cloudlinux.com/