performance over 100bT Ethernet?

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carlosg
Posts: 2
Joined: Tue Jul 05, 2005 12:13 pm

Tue Jul 05, 2005 12:21 pm

Most of the performance info I've read relates to using GbE... I've got a situation where I'm limited to 100bT, and looking to share only HDD to a couple of machines (no CDROMs or burners).

Would the performance be 1/10 of the numbers for GbE? 10-12 MB/s? Starport/starwind looks like a great way to do what I want, but would iSCSI be too slow?

Any input would be appreciated.

-Carlos
Val (staff)
Posts: 496
Joined: Tue Jun 29, 2004 8:38 pm

Tue Jul 05, 2005 5:19 pm

Hi Carlos,

Yes. for 100Mbit Ethrnet the network throughput is the weak point.
So all operations with an iSCSI drive are limited by the network speed.
Best regards,
Valeriy
carlosg
Posts: 2
Joined: Tue Jul 05, 2005 12:13 pm

Tue Jul 05, 2005 6:08 pm

Thanks for the response Valery.

So are you saying my estimate is correct (10-12MB/s)?? Is Starwind unusable without GbE?

-C
Val (staff)
Posts: 496
Joined: Tue Jun 29, 2004 8:38 pm

Tue Jul 05, 2005 7:27 pm

carlosg wrote:Thanks for the response Valery.

So are you saying my estimate is correct (10-12MB/s)?? Is Starwind unusable without GbE?

-C
Carlos,

No, it depends on what throughput you need.
StarWind's targets could be used without any problems with 100MbE.
For a home user or a small office the network speed is enough.

But if you wish to access an ImageFile target located on a high-speed RAID volume that allows local access say 40MB/s, the resulting iSCSI throughput still will be about 20-22 MB/s (for full-duplex 100MbE).

So as for a WLAN or a 10MbE connections - they are definitely nothing to do with iSCSI because of low network throughput, but 100MbE can be used with iSCSI (and is being used successfully by dozens of people).

Just let it a try. :)
(BTW StarWind allows 15 days trial period free of charge)
Best regards,
Valeriy
gbarnas
Posts: 2
Joined: Fri Jul 15, 2005 12:36 am
Location: New Jersey, USA

Fri Jul 15, 2005 2:34 am

Carlos,

Take the trial and experiment!

I was planning (and ultimately implemented) a dedicated Gig Ethernet LAN for the iSCSI connections between the servers, but tested it over the standard 100bT switched LAN and was impressed by the speed. My test was between a dedicated W2K3 storage controller and my XP workstation. It's a small test LAN - 6 servers & 8 workstations - but performance on the iSCSI attached disk seemed much faster than normal network shares.

I now have a Gig-E switch connecting 3 servers (web, Exchange, & SQL) to the storage server and am very happy with the performance. No hard numbers (yet) but seems at least equal to the FC SAN storage.

Glenn
Val (staff)
Posts: 496
Joined: Tue Jun 29, 2004 8:38 pm

Fri Jul 15, 2005 10:52 am

Glenn,

Thank you for the information confirming that iSCSI works good over a 100MbE network.

And yes, iSCSI works at least 2 times faster than network shares.
Best regards,
Valeriy
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