Methods for caching PHP objects to file?

Question

In ASPNET, I grew to love the Application and Cache stores. They're awesome. For the uninitiated, you can just throw your data-logic objects into them, and hey-presto, you only need query the database once for a bit of data.

By far one of the best ASPNET features, IMO.

I've since ditched Windows for Linux, and therefore PHP, Python and Ruby for webdev. I use PHP most because I dev several open source projects, all using PHP.

Needless to say, I've explored what PHP has to offer in terms of caching data-objects. So far I've played with:

1. Serializing to file (a pretty slow/expensive process)
2. Writing the data to file as JSON/XML/plaintext/etc (even slower for read ops)
3. Writing the data to file as pure PHP (the fastest read, but quite a convoluted write op)

I should stress now that I'm looking for a solution that doesn't rely on a third party app (eg memcached) as the apps are installed in all sorts of scenarios, most of which don't have install rights (eg: a cheap shared hosting account).

So back to what I'm doing now, is persisting to file secure? Rule 1 in production server security has always been disable file-writing, but I really don't see any way PHP could cache if it couldn't write. Are there any tips and/or tricks to boost the security?

Is there another persist-to-file method that I'm forgetting?

Are there any better methods of caching in "limited" environments?

Answer 1

Serializing is quite safe and commonly used. There is an alternative however, and that is to cache to memory. Check out memcached and APC, they're both free and highly performant. This article on different caching techniques in PHP might also be of interest.

Answer 2

It's in theory possible to store objects in sessions. That might get you past the file writing disabled problem. Additionally you could store the session in a mysql memory backed table to speed up the query.