On my Server both APC and Memcached is installed. I have enabled both caching system one by one from local.xml each time.
In both cases I have checked site speed from Google Page Speed and Gtmetrix Speed test but its showing tha same grade as previous.
Here my question is: How can I check site performance after enabled APC OR Memcached. Or How can I check its working fine or not.
Please Help !!
Best Answer
Pankaj,
Contrary to popular belief, neither using APC or Memcache as cache/session backends will make a noticeable difference to single-user page load time - unless you had a disk I/O bottleneck to begin with (meaning that the memory backed cache will outperform the slow disk based cache).
If you don't have I/O issues, then enabling them won't make a difference to the actual page load time.
Where they'll come into play is in high concurrency situations, synthetic benchmarks like Siege/AB will demonstrate this very clearly, with an almost 50% increase in request/s. How this translates to real-world performance however, isn't so dramatic.
You'll know if it is working if the
var/cache
directory is empty, and if using Memcache for sessions, if thevar/session
directory is empty.If you use file-backed
slow_backend
, then you'll still see cache tag data created invar/cache
- but not the cache data itself.Bottom line, if you are trying to improve page-load time performance, changing the cache store isn't going to make a noticeable difference unless your server's HDDs are so contrained that serving files from disk is a bottleneck.