FC2243 + MSA 1500 cs poor perfomance

[alextan]

Hi all.

here's my scenery:

A MSA1500 cs with 4 MSA20 SATA boxes connected. Volumes RAID 6 ADG on those disk.

2 servers can access that box:

DL385 G2 with A8003A FC Card, PCI-E-> GOOD PERFORMANCE

DL360 G4 with FC2243 FC Card PCI-X -> TERRIBLE PERFORMANCE

I used sqlbcksim tool to simulate sequential write con the box (I use the msa for disk backups)

Here are the details of the test. (200 GB but with 6 GB file even better results, I used 200 GB file just to be sure to avoid to use the controller or server cache)

T:\>sqlbcksim.exe t:\test 2 200000 1

File name = t:\test

Version = 2 , Backup Size (MB) = 200000

Write Back mode

Allocating 1MB

Memsetting 1MB

Opening file at 13:16:14

Writing headers

Writing data

Closing file at 13:22:04

Time elapsed (minutes):  5:50

Average throughput: 571.43 Mb/s

----

write just 6 GB file:

DL360 G4 PCI X 4 Gb emulex FC2243

K:\SQLBCKSIM>sqlbcksim r:\test 2 6100 1

File name = r:\test

Version = 2 , Backup Size (MB) = 6100

Write Back mode

Allocating 1MB

Memsetting 1MB

Opening file at 17:58:03

Writing headers

Writing data

Closing file at 18:00:57

Time elapsed (minutes):  2:54

Average throughput: 35.06 Mb/s

Sim Complete

----

The fact is on DL360 server, after 2 GB written (as fast as the DL385 server) , the write drops to about 20 MB/s, then stops, then write 20 MB,... and so on.

On MSA i use fw 7.20 A/A. I also updated the firmware and drivers on the fc2243 emulex card with no effect. I can't find crc errors on onecommand console, I also tried to change the fiber that connects the hba to the switch with no effect...

I also did some tests using sqlio benchmark with similar results.

Where's the problem? Why this huge difference?

Thank you all in advance for your help.

Alessandro

[alextan]

Another "confusing" info:

Another test: I connected another server, DL360 G5 server, with A8003A PCI-E hba.

With my surprise, the write performance is as slow as with DL360 G4 with FC 2243. :mansurprised:

In all the cases the Operationg System is Win2008 R2. All the tests have been made with latest drivers and firmwares.

The problem is not the LUN because I tried to move the same lun among the 3 servers: Slow with DL360 G4 and G5, fast with DL385 G2. The big difference is the Memory available, the DL385 has 16 Gb, while DL360s have only 4 GB. But I really believe the RAM is not the matter, because i tried to write a 200 GB file...

I am really confused...

Any ideas?