Gluster users - Oct 2011 - Optimal XFS formatting?

Hi,

Are there any 'optimal' settings for XFS formatting under GlusterFS? 
The storage will be used for Virtual Disk storage, virtual disk size from 8GB to
100 GB in size.

One of the VM's (separate gluster volume) will be running MSSQL server (4K
reads and writes).  The other will be running file servers, etc).

Thanks,
Gerald

Hi,

I've seen that EXT4 has better random I/O performance than XFS,
especially on small reads and writes. For large sequential reads and
writes XFS is a little bit better. For really large sequential reads
and write EXT4 and XFS are about the same. I used to format XFS using
this:

mkfs.xfs -l size=64m

(notes from
http://everything2.com/title/Filesystem+performance+tweaking+with+XFS+on+Linux)

but realized that it doesn't seem to effect performance for me. You
should definitely try mounting with this :

mount -t xfs -o rw,noatime,nodiratime,logbufs=8

HTH,
Sabuj

On Thu, Oct 20, 2011 at 8:18 AM, Gerald Brandt <gbr at majentis.com>
wrote:
> Hi,
>
> Are there any 'optimal' settings for XFS formatting under
GlusterFS? ?The storage will be used for Virtual Disk storage, virtual disk size
from 8GB to 100 GB in size.
>
> One of the VM's (separate gluster volume) will be running MSSQL server
(4K reads and writes). ?The other will be running file servers, etc).
>
> Thanks,
> Gerald
> _______________________________________________
> Gluster-users mailing list
> Gluster-users at gluster.org
> http://gluster.org/cgi-bin/mailman/listinfo/gluster-users
>

On 10/20/2011 03:18 PM, Gerald Brandt wrote:
> Hi,
>
> Are there any 'optimal' settings for XFS formatting under
GlusterFS?  The storage will be used for Virtual Disk storage, virtual disk size
from 8GB to 100 GB in size.
>
> One of the VM's (separate gluster volume) will be running MSSQL server
(4K reads and writes).  The other will be running file servers, etc).
hi,

Why do you use VM images for these IO demanding tasks?

Anyway, we use this script:

#!/bin/bash
BLOCKSIZE=4096 # Make sure this is in bytes
CHUNKSIZE=128  # Make sure this is in KiB
NUMSPINDLES=8
RAID_TYPE=6
RAID_DEVICE_NAME="/dev/sda4" # Specify device name for your RAID
device
FSLABEL="gluster" # specify filesystem label for generating mkfs line
here

case "$RAID_TYPE" in
0)
     RAID_DISKS=${NUMSPINDLES};
     ;;
1)
     RAID_DISKS=${NUMSPINDLES};
     ;;
10)
     RAID_DISKS=${NUMSPINDLES};
     ;;
5)
     RAID_DISKS=`echo "${NUMSPINDLES} - 1" | bc`;
     ;;
6)
     RAID_DISKS=`echo "${NUMSPINDLES} - 2" | bc`;
     ;;
*)
     echo "Please specify RAID_TYPE as one of: 0, 1, 10, 5, or 6."
     exit
     ;;
esac

SUNIT=`echo "${CHUNKSIZE} * 1024 / 512" | bc`
SWIDTH=`echo "$RAID_DISKS * ${SUNIT}" | bc`

echo "System blocksize=${BLOCKSIZE}"
echo "Chunk Size=${CHUNKSIZE} KiB"
echo "NumSpindles=${NUMSPINDLES}"
echo "RAID Type=${RAID_TYPE}"
echo "RAID Disks (usable for data)=${RAID_DISKS}"
echo "Calculated values:"
echo "Stripe Unit=${SUNIT}"
echo -e "Stripe Width=${SWIDTH}\n"
echo "mkfs line:"
echo -e "mkfs.xfs -b size=${BLOCKSIZE} -d 
sunit=${SUNIT},swidth=${SWIDTH} -L ${FSLABEL} ${RAID_DEVICE_NAME}\n"
echo "mount line:"
echo -e "mount -o remount,sunit=${SUNIT},swidth=${SWIDTH}\n"
echo "Add these options to your /etc/fstab to make permanent:"
echo "sunit=${SUNIT},swidth=${SWIDTH}"


Corresponding fstab:

/dev/sda4    /mnt/brick1    xfs    
delaylog,sunit=256,swidth=1536,logbufs=8,logbsize=256k,noatime,nodiratime    
0    0


tamas