We are moving our databases to an EMC CX320 but we do not have any recommendations on what file system to use on the SAN to support our large databases. We currently use ext3 but it has issues with really large partitions over 2Tb. We also have an issue with finding a file system that supports MySQL's "innodb_flush_method = O_DIRECT". A MySQL support rep suggested using Linux GFS but this seems to entail running the linux cluster software which sounds like overkill. Has anyone run a write and read intensive MySQL database on a SAN and if so have any tips on configuring the filesystem for such a load.