P800 + MSA70 MUCH slower than P800 + MSA60 ?

[Rory Niland]

I'm running a DL380 G5 ( single quad, 4GB RAM ) with 32 bit Win2K3 standard with a P800 attached to MSA60
The MSA60 is filled (12 disks) with 300GB 15K RPM 3.5 SAS disks running RAID 6 ADG

I'm also running a DL580 G4 ( 4 x dual core, 32GB RAM ) with 64 bit Win2K3 Enterprise with a P800 attached to an MSA70.
The MSA70 has 16 disks each are 146GB 10K RPM 2.5 SAS disks running RAID 6 ADG

both a running latest firmwares and PSP's.

I have an I/O tool that a software vendor gave me after I complained of the softwares performance on the DL580 - they blamed the I/O on the DL580 which I expected to be somewhat similar to the DL380 .. slower disks but more spindles.

here are the results :

DL580G4 :
Buffered Write speed: 16.29 MB/sec *****
Buffered Read speed: 24.69 MB/sec
Unbuffered Write speed: 123.42 MB/sec
Unbuffered Read speed: 182.56 MB/sec
Unbuffered Seek rate: 2395.03 seeks/sec
Context switch time: 14.61 ms

DL380G5 :
Buffered Write speed: 133.34 MB/sec
Buffered Read speed: 46.46 MB/sec
Unbuffered Write speed: 154.54 MB/sec
Unbuffered Read speed: 113.37 MB/sec
Unbuffered Seek rate: 2453.73 seeks/sec
Context switch time: 14.61 ms


The buffered write speed is pathetic (16 MB/sec) and is slowing everything down, I've enabled the write cache and tested changing the controller percentage read/write .. then I changed the stripe size .. NO appreciable difference.

Is there anything that anybody can recommend ?

[Proliantstud]

Hi,

Try changing the batteries (512 MB BBWC batteries) of the controller in 580 G4 in a scheduled down time. In most cases this will fix the issue. This may sound crazy but it works.

The part number is 398648-001
Battery charger module - For HP Smart Array P400, P600, and P800 controllers


To further increase the performance, make the memory as 1GB.
Part number for memory 398646-001
1GB DDR2 DIMM memory module

I hope the above config will beat the record write speed of your DL380 G5. Best wishes.
Cheers,
Anand

[Rory Niland]

The P800 in the DL580 is Brand new .. only a couple of days old. It's status is also good according to the array diagnostic utility and if I disable the cache on the controller the performance drops to 2MB/s!

Ergo the cache is working and therefore the controller thinks the battery is ok.

But I will change the battery if you know of some issue with these cards and their batteries from new ?

[Proliantstud · Accepted solution]

Hi,

Since it is a new controller, the batteries will take 72 hours to fully charge. Run the test after 72 hours of P800 installation and check the buffered write speed.

There was a similar issue (Same issue) with a High Performance Computing cluster environment with a new P800 on a DL585 G5 Storage server. The HP engineers replaced the Battery and resolved the issue with no explanation!

I will let you know the reason after a research. Will reply soon with an explanation.

Cheers,
Anand

[Rory Niland]

Rebuilt as a RAID 5 array with a hot spare and the speed is a lot better. Not sure if the P800 just *started* working ?

left the stripe size as 64K and 50:50 read write priority.

Are results are now

Buffered Write speed: 158.77 MB/sec **
Buffered Read speed: 81.26 MB/sec
Unbuffered Write speed: 170.21 MB/sec
Unbuffered Read speed: 263.24 MB/sec
Unbuffered Seek rate: 3633.00 seeks/sec
Context switch time: 14.61 ms

thanks for your help.