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 ....??
Thanks.
carlopmart 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 ....??
None of them should have a problem with large files and any differences in the filesystem metadata handling will be covered up by the underlying disk access speed of a large amount of data per file. The bigger differences are in how fast they can create or delete large numbers of files.
Les Mikesell wrote:
carlopmart 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 ....??
None of them should have a problem with large files and any differences in the filesystem metadata handling will be covered up by the underlying disk access speed of a large amount of data per file. The bigger differences are in how fast they can create or delete large numbers of files.
Thanks Les. then if I would to use sparse files to create these large files, which can be the best form: dd of qcow2 format for example??
On Wed, Dec 23, 2009 at 10:47 AM, carlopmart carlopmart@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
Kwan Lowe wrote:
On Wed, Dec 23, 2009 at 10:47 AM, carlopmart carlopmart@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...
carlopmart wrote:
Kwan Lowe wrote:
On Wed, Dec 23, 2009 at 10:47 AM, carlopmart carlopmart@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.
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...
I actually prefer backing up LVMs.. I use the snapshot feature which means I can backup a live volume. Works well.
Kwan Lowe wrote:
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...
I actually prefer backing up LVMs.. I use the snapshot feature which means I can backup a live volume. Works well.
But I can't use snapshot feature because under these lvm partitions there are ZFS, NTFS and so on filesystems that linux can't access ...
I actually prefer backing up LVMs.. I use the snapshot feature which means I can backup a live volume. Works well.
But I can't use snapshot feature because under these lvm partitions there are ZFS, NTFS and so on filesystems that linux can't access ...
Not sure that I'm understanding.. The snapshots are block level, so no knowledge of the filesystem on the LVs are needed. In fact, some are raw devices and don't have filesystems at all.
On Wed, Dec 23, 2009 at 2:50 PM, carlopmart carlopmart@gmail.com wrote:
Kwan Lowe wrote:
I actually prefer backing up LVMs.. I use the snapshot feature which means I can backup a live volume. Works well.
But I can't use snapshot feature because under these lvm partitions there are ZFS, NTFS and so on filesystems that linux can't access ...
There is a perfectly usable NTFS support file system available for CentOS/Linux - I use it from time to time for disk backups.
Take a look at NTFS-fuse.
BTW, volume backups generally do not require knowledge of the underlying file system structures, so this shouldn't be an issue anyway.
mhr
-
carlopmart -
Kwan Lowe -
Les Mikesell -
MHR