|
Home > Archive > Data Storage > October 2005 > ax100 and lefthand medoicre iscsi performance
You are viewing an archived Text-only version of the thread.
To view this thread in it's original format and/or if you want to reply to
this thread please [click here]
| Author |
ax100 and lefthand medoicre iscsi performance
|
|
|
| I'm looking for some insight from people out there using iscsi.
We're experimenting with it where I work, but the two solutions we've
been testing so far haven't delivered great performance.
We're using Windows 2k3 on some 3.x ghz dl320g3 servers, with one of
the gigabit nic's connected to a catalyst 4006 dedicated to a private
iscsi network.
We're testing the emx ax100i and some stuff from lefthand, and
performance seems to top out at ~25MB/s reading or writing. That's
kinda sad since I can get that performance from a built in sata drive.
We're using the latest iscsi initiator from microsoft.
We have 4 drives setup on lefthand in a raid0 with 2 way replication.
We also have 4 drives setup on the emc in a raid5.
I know these aren't set up apples to apples, but that's how my boss has
them set up.
Has anybody else seem similar results?
We purchased some adaptec gigbit iscsi nics to see if this helps, but
I'm guessing that it won't do that much.
We're not using jumbo frames, as the cards in the 4006 don't support
it.
I'm just looking to see what kind performance people have been getting,
and what they've been using.
thanks..
rgt
| |
| Rob Turk 2005-09-28, 2:47 am |
| "rgt" <crackwookie@gmail.com> wrote in message
news:1127856489.890053.194590@f14g2000cwb.googlegroups.com...
> I'm looking for some insight from people out there using iscsi.
> We're experimenting with it where I work, but the two solutions we've
> been testing so far haven't delivered great performance.
>
> We're using Windows 2k3 on some 3.x ghz dl320g3 servers, with one of
> the gigabit nic's connected to a catalyst 4006 dedicated to a private
> iscsi network.
>
> We're testing the emx ax100i and some stuff from lefthand, and
> performance seems to top out at ~25MB/s reading or writing. That's
> kinda sad since I can get that performance from a built in sata drive.
>
> We're using the latest iscsi initiator from microsoft.
> We have 4 drives setup on lefthand in a raid0 with 2 way replication.
> We also have 4 drives setup on the emc in a raid5.
>
>
> I know these aren't set up apples to apples, but that's how my boss has
> them set up.
>
> Has anybody else seem similar results?
> We purchased some adaptec gigbit iscsi nics to see if this helps, but
> I'm guessing that it won't do that much.
>
> We're not using jumbo frames, as the cards in the 4006 don't support
> it.
> I'm just looking to see what kind performance people have been getting,
> and what they've been using.
>
> thanks..
>
> rgt
>
You just answered your own question. You are not using Jumbo frames. That
means your maximum transfer rates are seriously impeded by TCP/IP handling
overhead.
Rob
| |
|
| Thanks for the reply. I wasn't sure how bad the throughput would be
without jumbo frames, and the 4006 was what I had available. I'm in the
process of getting some hardware that supports jumbo frames, so I'll
reply back with an update on any performance improvements.
thanks..
rgt
| |
| Rob Turk 2005-09-28, 5:54 pm |
| "rgt" <crackwookie@gmail.com> wrote in message
news:1127920446.550922.304750@g44g2000cwa.googlegroups.com...
> Thanks for the reply. I wasn't sure how bad the throughput would be
> without jumbo frames, and the 4006 was what I had available. I'm in the
> process of getting some hardware that supports jumbo frames, so I'll
> reply back with an update on any performance improvements.
>
You could try running a point-to-point connection to see how much impact the
switch has. Use a cross-over cable to hookup a server to the AX100 directly
Rob
| |
| Eric.Jones 2005-09-29, 2:49 am |
| rgt wrote:
> Thanks for the reply. I wasn't sure how bad the throughput would be
> without jumbo frames, and the 4006 was what I had available. I'm in the
> process of getting some hardware that supports jumbo frames, so I'll
> reply back with an update on any performance improvements.
>
> thanks..
> rgt
>
Your're on the right track with a dedicated GigE switched network,
thus avoiding the headaches of trying to coexist with existing LAN traffic.
But look carefully at which line cards you will use on the switch.
The cisco WS-65xx-GE series for example are 8:1 oversubscribed, intended mainly
for wiring closed aggregation of low-utilization devices. And check the buffer
size per port as well, it can vary from 1+ MB per port down to 128K.
Of course the better performing line cards (like the WS-X6748-GE) are more
expensive, and require the Sup720 supervisor card (more $$$) but can provide
full line rate on every port, with enough buffer to avoid congestion slowdowns.
Not much help if you are assembling from spare cards and chassis that are just
lying around unused. But good luck, and keep us posted!
Eric
| |
| Dave Sheehy 2005-10-24, 9:44 am |
| Rob Turk (_wipe_me_r.turk@chello.nl) wrote:
: "rgt" <crackwookie@gmail.com> wrote in message
: news:1127856489.890053.194590@f14g2000cwb.googlegroups.com...
: > We're not using jumbo frames, as the cards in the 4006 don't support
: > it.
: > I'm just looking to see what kind performance people have been getting,
: > and what they've been using.
: >
: > thanks..
: >
: > rgt
: >
: You just answered your own question. You are not using Jumbo frames. That
: means your maximum transfer rates are seriously impeded by TCP/IP handling
: overhead.
But, less than 10% of real world networks have Jumbo Frames enabled so if
you're depending on Jumbo Frames for performance you're most likely SOL.
Dave
|
|
|
|
|