When upgrading code, object (or DB?) cache holds on to old versions
|Reported by:||Ipstenu||Owned by:|
|Component:||Cache API||Keywords:||needs-patch needs-unit-tests|
This is NOT a 3.8 bug, as I've seen it before, but now it's a little more prevalent. In seaching for enough forum posts, I tracked it all the way back to 3.5...
Scenario: You have object caching (APC, memecached, whatever) and when you upgrade via the UI, all the files get correctly downloaded -however- WP gets 'stuck' on a wrong screen. For example, one user was stuck on 'Your DB upgrade is complete' while another kept being told that 3.8 was ready to be installed, even though he'd already done it. In all cases, the files were verifiably WP 3.8, and it was just the cache being 'greedy' on the UI.
In all cases, flushing the server-side cache resolved the issues.
Caching Plugins: Of course this only happened with a site using a caching plugin, but it was not the same one. Batcache and Memcached Redux were the two I spotted.