cachingmemcachedlibmemcached

Memcached "get" returns nothing, but "cachedump" returns the key

I use memcached to store some HTML files, but sometimes I cannot retrieve them. I am using telnet to connect to memcached.

I run stats cachedump <slab> 0 which gives me an output similar to

ITEM mobile-https://local.master.lan/url-path-1 [232372 b; 1509033796 s] ITEM mobile-https://local.master.lan/url-path-2 [241813 b; 1509033790 s]

and then get mobile-https://local.master.lan/url-path-1

sometimes it outputs actual HTML, but some other times, it outputs nothing, it just says END.

I check the expiration time and it's not expired, I have no idea why for some keys memcached returns nothing.

Using CentOS 6.9

Solution

  • The problem was that memcached ran out of memory and deleted some value to make room for new ones being added. Setting the CACHESIZE to a higher number fixed the issue.