[Linux-cluster] Ext3/ext4 in a clustered environement

[Nicolas Ross]

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> On some services, there are document directories that are huge, not that 
> much in size (about 35 gigs), but in number of files, around one million. 
> One service even has 3 data directories with that many files each.

(...)

We're leaning towards changing the file system for those document 
directories (agian hierachy of, not 1 mil files per directory ;-) to ext4.

One or two question pops in my mind.

1. Can a node mount the volume read-write, while another one mount it 
read-only ?

2. I curently experience intermitent high i/o contention on the volume 
containing this data, the website still responds fase, but images takes more 
time to load when it arrives. I highly suspects, that since it's a ton of 
files spread trough out the disk, the it's the added latency of GFS that 
causes my problem.

So, how will perform an ext4 files over fiber versus a local one ?