I was looking into slowness working with bugtracker on openacs.org and analyzed the workflow package to figure out why it takes 30 seconds to close a bug.

I tracked it down to multiple calls to util_memoize_flush_regexp in workflow.

That procedure loops over all the util_memoize cache entries, in this case 400,000 of them, and performs several regexp on them.

This is obviously very slow. I don't recommend using this procedure in any busy site.

The 400,000 cache entries only take up 9mb so you can easily get a huge number of cache entries with a relative small total cache size.

How would that work?

Don suggested using the db_* cache feature which will also greatly simplify the code.

Dave

So far all the calls to util_memoize_flush_regexp could use ns_cache names *pattern* instead. I am testing if there is a big speed difference.