We've got a centralised file cache which a cluster of web servers use to store "heavyweight" pages. Each webserver uses Samba to mount this shared area.
We're getting a lot of iowait on the server, and I wondered what steps we could take to make a more efficient centralised cache? We're already using memcache as first line cache for some objects, and may simply throw more memory at that, but I'm interesting in finding out what techniques we could use to speed up a file based cache. All the servers run recent release of Ubuntu.
The server uses an ext3 filesystem with LVM. Maybe other filesystems would be more performant for this sort of activity? We used Samba for many years simply because everyone is comfortable with it and we had maintenance headaches with NFS (refusal to unmount, for example). Maybe there's better technologies...