Sharing data across sessions?

littlebigman

Hello

A friend of mine is running a site that has about 1,000 concurrent users when it's really busy. Until now, he kept data in sessions (including output from SELECT fetched from a remote MySQL server), but since most data is the same across users, he tried MemCacheD... but performance is worse than calling MySQL again and again and using a lot of RAM to keep this into sessions.

Do you know of other ways to share data across users? What about shared memory?

Thanks for any tip.

cahva

Well I personally have used file based caches like Cache Lite which is a Pear class and Zend Framework's cache. Both are very good. Check those links that I gave you to get an idea how those work. I've made couple of high traffic sites and quite a lot of times mysql is almost idle because pages or portion of the pages are fetched from cache.

You can also use APC (Alternative PHP Cache) to get some extra boost. That one caches PHP code and works very well if the site is very cpu intensive. We had one site on one virtual server that actually came unresponsive (no ssh or console) and had to restart the virtual server from time to time. When we installed APC in it, no more restarts. PHP codes dont take much memory to cache so APC's memory usage is somewhere about 3-4 Megs with 3 (popular) sites on the server.

littlebigman

Thanks for the input. Cache_Lite is no longer maintained, but I'll look at Zend Framework if it's affordable.

APC looks like an interesting alternative to MemCacheD, and should offer better performance since data is local to each Apache server.

Thanks.

Weedpacket

littlebigman wrote:
....using a lot of RAM to keep this into sessions

That's why there is a "Mem" in "Memcached" 😃

Last time I used Memcached I found it made a huge improvement, as long as I didn't keep emptying it out.

cahva

Thanks for the input. Cache_Lite is no longer maintained, but I'll look at Zend Framework if it's affordable.

Oh, didnt notice that 🙂 Fortunately it says:

Bug Summary
No open bugs

😃

One more thing, APC is not compatible with Zend Optimizer(when I last checked) which we have to use on most of our servers due to some of our clients needs. So check first that if its installed before enabling APC.

Zend cache + APC should be a good combination.