I have multiple webservers which use many small files to created dynamic web pages. Caching the web pages isn't an option. The webserver also performs writes so I need a synchronous filesystem.

I'm looking to maximise performance as it's my understanding that small files is the weakness (to varying degreess) of a cluster filesystem over ethernet.

Currently I'm using Centos 5.5, 64 bit.

Since it's only about 300MB of data, I'm looking at mdadm using RAID-1 with the GNBD and a local hard disk using the "--write-mostly" option so the reads are done using the local hard disk.

Is this possible?

If so, is there any advantage to making it a tmpfs disk instead of a local hard disk?

Or will the files on the local hard disk just get cached in RAM anyway so I won't see a performance gain by using tmpfs, assuming there's enough RAM available?