[Gluster-users] infiniband speed
Nathan Stratton
nathan at robotics.net
Tue Jan 11 15:44:58 UTC 2011
On Mon, 10 Jan 2011, Joe Landman wrote:
> Try this:
>
> # (on bravo)
> dd if=/dev/zero of=/cluster/shadow/big.file bs=1M count=20k
>
> This will write a 20GB file to the same partition. We need to see how fast
> that write is (outside of cache)
>
> Do the same test on the other machine.
>
> Infiniband won't make slow disks fast. So unless you are already getting a
> gigabyte or two per second (we do on our units), adding Infiniband won't get
> you any significant additional performance.
>
> Put another way, you are bound by the slowest aspect of your storage system.
>
> What are your underlying disks? Are these individual drives? RAID? What
> sort of RAID if it is a RAID? How is it organized?
>
> We tune our systems pretty hard, so we start with 2+GB/s for TB sized files
> before we ever touch the next stack up. Each additional stack you traverse
> takes performance away (you lose it in stack inefficiency). So you should
> start out with as fast a system as you possibly can, so you don't lose too
> much performance.
What hardware gives you 2+GB/s? I am using the 16 port 3Ware 9750 cards
with fast drives and I dont get close to that.
-Nathan
More information about the Gluster-users
mailing list