ML350G4p + P600 SLOOOOOOOWWWWWW

[Chi Wai Lee]

I've got a ML350G4p with 2 * 3.4 Xeons and 6GB RAM. The OS is Win2003 Server x64 R2and boots off the SCSI drive.

The P600 is attached to 6 SATA 250GB drives.

I have a problem where the drives attached to the P600 are terribly slow at writing.

I get great results reading from the array but no matter what RAID type, the writes are always slow.

e.g. 1 Disk RAID0 gives me writes of 7MB/s, 2 Disk RAID0 = 10MB/s, 3 Disks RAID5 = 14 MB/s

[Gus Kwong]

Hi Chi-Wai,

That is really slow! You have mentioned about 6 SATA drives --- are they all linked together? I think the spec doc mentioned about upto 4 devices for a channel without expander.

Thanks,

Gus

[Chi Wai Lee]

The drive cage of the ml350G4p supports 6 hotswap SATA. Six drives are installed (all the same type). The P600 contains 2 connectors (each with 4 lanes) and both of these are connected to the drive cage.

I've had the P600 replaced with no difference from the new one. Installing Fedora Core 4 also produces similar slow performace.

Read performance however is superb and exactly as I expect.

[Gus Kwong]

Umm... there is a doc about performance on near/over 2TB logical drive, but does not really apply to you (have a look anyway):

http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?lang=en&cc=us&taskId=110&prodSeriesId=466290&prodTypeId=329290&prodSeriesId=466290&objectID=c00564367

What is your firmware version number?

[Chi Wai Lee]

Latest 1.20A firmware. Also latest driver.

Already read that doc, doesn't apply.

If I attach two of the drives to the motherboards SATA socket and get windows to stripe them, I get ~120MB/s read and write.

This is true whether the drive cage is involved or if the SATA drives are attached directly.

[Gus Kwong]

Arrh!! did you use the SATA cable came with the server? They are designed for the onboard/6port-SATA-Raid controller.

Can you confirm the part number of the cable between the drive cage and P600 has "389662-B21" printed on it?

If you bought P600 separately you need to buy two optional SAS cables.

[Chi Wai Lee]

I have a pair of the SAS to SATA (P600 connector to 4 individual SATA cables) and SAS to SAS cable.

The SAS-SAS cable connects the P600 to the drive cage and has the same connector on both ends with an id of 361316-007

[Gus Kwong]

I got a funny feeling we are on the course of tracing the root of the problem. I come across this doc about P600 optional cables. Have a look at the forth entry, under "additional cables required".

http://h20000.www2.hp.com/bc/docs/support/SupportManual/c00310097/c00310097.pdf?jumpid=reg_R1002_USEN

I hope this will solve your problem! If it does, don't forget to assign points! ;)

[Chi Wai Lee]

361316-007, 3889953-001 and 389662-B21

Above codes appear to be the same cable (SAS to SAS multilane)

http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?lang=en&cc=us&objectID=c00357508&jumpid=reg_R1002_USEN

[Gus Kwong]

Umm... your link did not show the part number you have mentioned... Anyway, what you need is two SAS/SATA multilane optional cables. If you search for "SAS cable" on HP Partsurf (UK), you will only find part number "389662-B21".

http://partsurfer.hp.com/cgi-bin/spi/main?sel_flg=modsrch&template=main&cpric=&prodsrch=SAS+CABLE

Hope this helps!