i'm building an email system and considering some filesystem that support online-resize, safe when power-outage, and does not restrict number of files per directory(or at least can hold some millions file per directory)
I want to know which filesystem is best for this situations. Can you help me,pls? Thanks in advance!
PS: i'm layering for my email storage as:
Layer-3: Filesystem(XFS,JFS,Btrfs,Reiser4,...) on top of drbd(/dev/drbd0)
Layer-2: DRBD(Dual-primary mode) on LVM2's logical volume
Layer-1: LVM2 on physical volume(/dev/sdc,/dev/sdd,...)
Layer-0: physical volume(sdc,sdd,...) is Hardware RAID10(with "Write-cache mode" is enabled) (each "physical volume" actually is 4 HDD)
Another question: Do you see something wrong in my design?
Edited: i'm using Ubuntu 12.04 LTS with 3.2 kernel.