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memcached evictions though memory is available

Ran into a performance issue where we would see intermittent slowness on application and it was traced to memcached evictions. Running stats command on memcached telnet port gave

STAT limit_maxbytes 8589934592
STAT bytes 6792297037
STAT total_items 1149728020
STAT evictions 192571322

As you can see even though close to 1G of memory is free we were seeing evictions. This article explained this in great detail and cleared some of my concepts
http://www.mikeperham.com/2009/06/22/slabs-pages-chunks-and-memcached/




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