We have our cache timeout set to 4500 seconds, and garbage collection runs hourly.
We're running a multi-site setup with about 90 sites.
So once an hour it wipes out our cache and server strain skyrockets for a few minutes.
I'd like to figure out a way to clear cache on a finer grained level. For example, when a post is created, flush just the archive pages for the site on which the post is made.
Then make WPSC run garbage collection once daily or something, because other stuff would be cleared out by something else.
Any suggestions for this? I'm comfortable writing some pretty hairy PHP and I know WordPress well.