Performance

[synthicate]

Hi,

I've recently installed the StarWind Pro on a server running Windows 2003 R2 (Enterprise). When I tried to connect the clients (running Win XP) thru Windows iSCSI and StarPort, I couldn't get more than 5MB/s read/write to the harddrives. The network is entirely gbit, and I get 50-65 MB/s when mounting a RAMDisk. I've tried mounting the harddrives as SPTI and Direct Bridge, but it seems as the performance is "stuck" at 5MB/s (constantly 5MB/s and a perfectly flat line when measuring the bandwidth). Any suggestions?

Best regards
André

[anton (staff)]

This is unacceptable. You should get 10-15% less then local hard disk does on the target.

What about image file with the buffering set to "OFF"?

What tool do you use to measure the performance?

[synthicate]

When buffering set to ON the transfer became very erratic (left graph). When turning OFF the buffering I got pretty good results (right graph). The tool used is Bandwidth Monitor Pro.



Left: Buffering=ON, Right: Buffering=OFF

[anton (staff)]

So image file with the buffering set to OFF is OK for you? Can you provide the same graph for the SPTI and DiskBridge share mode. Thanks!

[synthicate]

Thanks for your reply, Anton! I'm fine with no buffering on image files, as long as the transmission is steady and fast. Here are the two more graphs:


Left: SPTI, Right: DiskBridge

The file being transferred in all cases is a 5GB-file

[anton (staff)]

Both SPTI and DiskBridge should not work that slow. I'll bring Valery to look at this issue later today.

I'd suggest you to check the same configuration with the I/O meter.

[synthicate]

Think I've narrowed it down to the RAID-controller. Tried to create an image-file on one of the RAID-partitions, and the transfer-rate never reached more than 5MB/s (strange thing though, having 45MB/s on other partitions).

There might be some issues when transferring large files, so I'll examine the hardware closer. Don't think the problem lies within the StarWind, as I first thought, but will keep you updated in case someone else has the same problem Thank you for your support!

[anton (staff)]

We're acting as a bridge software. So we can add a little bit of the latency, make things run smoother but not with so dramatical drops Good idea is to tune local disk I/O subsystem and network stack and do SAN only after makings sure they both work fine.