[CentOS] OT:Which filesystem to use with large files

Les Mikesell lesmikesell at gmail.com
Wed Dec 23 17:29:58 UTC 2009

carlopmart wrote:
> Kwan Lowe wrote:
>> On Wed, Dec 23, 2009 at 10:47 AM, carlopmart <carlopmart at gmail.com> wrote:
>>> Hi all,
>>>  Recently I have installed a centOS 5.4 server to use as a home NAS server. I need
>>> to use large files (8GB minimum) inside of it to serve via iSCSI services. Which
>>> filesystem do you recommends me to reach maximum performance: xfs, ext3, ext4, gfs2
>>> ....??
>> I don't know if this is still true, but when I last checked a couple
>> years ago, the recommendation was for LVM device backed iSCSI targets.
>> http://osdir.com/ml/linux.iscsi.tgt.devel/2008-09/msg00000.html
>> With LVMs you'd of course lose the flexibility of file-backed targets
>> and the ability to do sparse files are you're intending..
>> dd if=/dev/zero of=iqn.2009-12.com.mydomain:storage.disk01.foo.foo
>> bs=1 count=0 seek=16G
> LVM was my first option and performance it is very very good with iSCSI, but backup 
> and restore it is a problem with LVM. For these reason I need to use large files on 
> this server...

Doesn't sparse file use leave you in danger of (a) overcommiting the 
actual available space, and (b) badly fragmenting the on-disk locations 
when the space is actually allocated?   I think xfs has some support for 
allocating sparse space at creation time without waiting for real 
writes, but I don't know how to use it.

   Les Mikesell
    lesmikesell at gmail.com

More information about the CentOS mailing list