It should be better now. I attach the diagnosis and cure from one of the admins.
Best wishes
Adrian
--------------------------------------------------------------------------------------------------------------
I took a look. I noticed very high disk I/O on the /data drive.
Some aggressive web-spiders were crawling the rss feeds and individual posts,
causing them to be re-cached, and bloating the size of the on-disk cache.
The cached files are stored in a directory hierarchy that's based on the
32-character md5 hash of the key, split into 3-character segments, so
each cache hit(or miss) would cause over 13 stat() calls to hit the disk.
I patched the forums/htdocs/includes/cache/file.php code to split the
hash into 3 segments that are 3, 3, and 26 characters long, so that the cache
directory hierarchy is 3 directories deep, instead of 11.
Blocking the worst of the web web-spiders combined with the shallower cache-tree
has brought the disk I/O back down to sane levels, and forums are loading faster.
