Should you cache?

[dormando]

Should you use memcached? Should you just shard mysql more?

Memcached's popularity is expanding its use into some odd places. It's becoming an authoritative datastore for some large sites, and almost more importantly it's sneaking into the lowly web startup. This is causing some discussionMost of whom seem to be missing the point. In this post I

Comments

Great Post - Thankyou

[geoffmcqueen]

Alan,

Great post - don't apologise for quality taking time, and thanks for writing it!

Geoff

[deflatermouse]

+1

[powerlord]

Nonsense, memcached is a panacea for everything!!!!111

[pyrop]

Memcached fixed my cat's flea problem. No joke!

[sodabrew]

Mine too! It seems the fleas kept checking for $flea->has_kitty, and because I was keeping the canonical state of the $flea object in memcached, and I had a system failure on that box, I lost all the state records and killed all the $fleas.

[boogabee]

I have to agree with the thought that memcache does not scale your website. I'm fighting consistently to stop the notion that a horrible sql query doesn't matter because we'll memcache the result. Putting memcache in front of bad backend design is not a fix, it only masks the problem for a short amount of time. An additional fight that I run into is that memcache is a data repository you can depend upon. I run into the idea that people can stash things there and then come back at any time and get it dependably. I'm not sure if this is just my environment or a more widespread view. I love memcache, but I'm seeing it used in many ways and instances where it shouldn't.

Should I use memcached?

[diamondeagle]

I'm a bit confused...

I'm running a PHP web application (Moodle) on a Windows 2003 Server machine. It uses a MSSQL 2005 database on a separate database server. I've configured PHP to run with eAccelerator. Should I also be using memcached?

Can I run eAccelerator AND memcached?