Gluster users - Nov 2016 - Improving IOPS

2016-11-05 9:52 GMT+01:00 Lindsay Mathieson <lindsay.mathieson at
gmail.com>:
>  pool: tank
> config:
>         NAME STATE     READ WRITE CKSUM
>         tank ONLINE       0     0     0
>           mirror-0 ONLINE       0     0     0
>             ata-WDC_WD6000HLHX-01JJPV0_WD-WX41E81ZU901 ONLINE       0     0
> 0
>             ata-WDC_WD6000HLHX-01JJPV0_WD-WX81E81AFWJ4 ONLINE       0     0
> 0
>           mirror-1 ONLINE       0     0     0
>             ata-WDC_WD6000HLHX-01JJPV0_WD-WX41E81ZV240 ONLINE       0     0
> 0
>             ata-WDC_WD6000HLHX-01JJPV0_WD-WX41E81ZV027 ONLINE       0     0
> 0
>           mirror-2 ONLINE       0     0     0
>             ata-WDC_WD6000HLHX-01JJPV0_WD-WX41E81ZU903 ONLINE       0     0
> 0
>             ata-WDC_WD6000HLHX-01JJPV0_WD-WXB1E81EFFT2 ONLINE       0     0
> 0
>           mirror-4 ONLINE       0     0     0
>             ata-WDC_WD30EFRX-68EUZN0_WD-WCC4N1UFDFKA ONLINE       0     0
> 0
>             ata-WDC_WD30EFRX-68EUZN0_WD-WCC4N7ZKLK52 ONLINE       0     0
> 0
>         logs
>           ata-KINGSTON_SHSS37A240G_50026B7267031966-part1 ONLINE       0
> 0     0
>         cache
>           ata-KINGSTON_SHSS37A240G_50026B7267031966-part2 ONLINE       0
> 0     0

Which is the advantage by using a single RAID-10 (thus 1 brick per
server) and not 1 brick per each RAID1 volume?
In the first case, ZFS is aggregating volumes, in the second, gluster
is aggregating volumes.

With gluster, healing should be faster in case of failure. If you
loose a mirror, you have to resilver the whole RAID-10 from network,
by using ZFS and RAID-10
With gluster, if you loose a mirror, you have to heal only that one.

On 5/11/2016 7:02 PM, Gandalf Corvotempesta wrote:
> With gluster, healing should be faster in case of failure. If you
> loose a mirror, you have to resilver the whole RAID-10 from network,
> by using ZFS and RAID-10
> With gluster, if you loose a mirror, you have to heal only that one.
Six of one, half a dozen of the other. With RAIDZ10 I can lose one disk, 
maybe two without losing the brick. Replacing the disk is very easy and 
fast.


Resilvering one disk in a raid10 set is a lot quicker and less impact 
than resyncing a brick via the network.

-- 
Lindsay Mathieson