Benchmarking SANs

Lanz · 12 Apr 2011 at 12:45

Using ATTO, what kind of setting should I choose to get some good basic performance figures from 2 different SANs (FC vs iscsi)?

Every setting I choose on the FC setup, brings back simular results, but changing the queue depths and IO setting on the iscsi SAN bring back very different results.

Could anyone suggest any recommended settings? Or even another tool for comparing the 2 SANs.

s0ck · 12 Apr 2011 at 14:27

Dunno but I'd like to see the ATTO screenies if poss

Lanz · 12 Apr 2011 at 15:35

s0ck · 12 Apr 2011 at 15:55

Top one looks very consistent as per any other HDD bench. Bottom one looks broke

Lanz · 12 Apr 2011 at 15:57

Yes, its very odd... that's Lefthand networks for you.

But look at the 4K QD32, that would suggest it shines when put under massive load using multiple servers, but it doesnt perform on a per server level like FC would.

s0ck · 12 Apr 2011 at 16:05

I'm a simple read/write whore

Massive cache on the LH kit skewing the QD32 test, possibly?

Lanz · 12 Apr 2011 at 16:07

s0ck said:
I'm a simple read/write whore

Massive cache on the LH kit skewing the QD32 test, possibly?

The LH does have 96 SAS disks in play, so it potentially scales out without any performance hit.

DustyMiller · 12 Apr 2011 at 16:15

Also does the iScsi server / connection have its own dedicated iSCSI HBA, or are you ising built in NIC's. That will have a major impact on the data processing.

Lanz · 12 Apr 2011 at 16:34

Built in flex10 nics on the servers, they have the option for converting to HBA via the virtual connect, but it wasnt recommended as the lefthand DSM driver doesn't work well with HBAs (according to HP)

akakjs · 12 Apr 2011 at 20:56

Can I ask how you've got the switching configured? (Trunking/flow control/jumbo frames).

Also how do you have the network raid configured?

Excuse the questions but I maybe ordering a left hand cluster on Monday

akakjs

ThorpedoUK · 13 Apr 2011 at 00:04

Indeed jumbo frames = big gain (but you probably know this already) and etherchannel / link aggregation, SW/HW iSCSI at the server?

Lanz · 13 Apr 2011 at 13:42

Flow control is on.
No Jumbo frames (was recommended, dont ask me why...)
ALB bonding, but we might try 802.3ad on each node.

SW initiators.