6 Replies Latest reply on Aug 31, 2010 3:48 PM by BigWaveware

Poor disk performance - IBM HS22 blades w/ mirrored 500 GB SAS drives

shmick75 Jun 8, 2010 2:34 PM

I've got a bunch of ESXi 4 installs on IBM HS22 blades with 146GB drives that work great. I've got 2 new HS22 blades with 500 GB SAS drives and the disk performance is terrible.

The hosts are all running Ubuntu Server 9.10 and 10.4 64bit. I noticed something was up right away when it took almost 10 minutes for the Ubuntu install to format a 200GB partition.

Any type of disk load ie: untaring a 2GB file and the server comes to a crawl with extremely high I/O waits.

I realize that 500GB drives will be a little slower, but this is extremely slow.

Hoping to get this resolved soon.

1. Re: Poor disk performance - IBM HS22 blades w/ mirrored 500 GB SAS drives

shmick75 Jun 8, 2010 8:55 PM (in response to shmick75)

A little more info on the setup.

Server = IBM HS22 Blade. 24 GB Memory, 2 x Intel 5530 quad core processors, 2 x 500GB SAS drives, hardware mirrored. Firmware and IMM on the blade are at latest versions (UEFI = 1.08, IMM = 1.10)

ESXi = 4.0.0 build-256968 -Initial install was done from 'ESXi 4.0 U1 with IBM Customization' VM = 12GB Memory, 4 CPUs, 200GB disk from the 500GB local mirror.VM OS = Ubuntu 10.4 64bit
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2. Re: Poor disk performance - IBM HS22 blades w/ mirrored 500 GB SAS drives

Steven Bright Jun 15, 2010 11:41 AM (in response to shmick75)

The 146GB SAS drives are not the same as the 500GB NL SAS drives.

From IBM's option guide for the HS22 (http://www-03.ibm.com/systems/xbc/cog/bc_hs22_7870/bc_hs22_7870hdd.html):

42D0632 - IBM 146GB 10K 6Gbps SAS 2.5" SFF Slim-HS HDD
42D0677 - IBM 146GB 15K 6Gbps SAS 2.5" SFF Slim-HS HDD
42D0707 - IBM 500GB 7200 6Gbps NL SAS 2.5" SFF Slim-HS HDD

As you can see, the 146GB drives come in 10K and 15K RPM and the 500GB is only available in a 7200RPM. Additionally, the 500GB drive is a nearline (NL) SAS drives which is basically a SATA hard drive with a SAS interface board. These drives are great for large amounts of data, but do not provide the same performance as the 10K and 15K RPM SAS drives.

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3. Re: Poor disk performance - IBM HS22 blades w/ mirrored 500 GB SAS drives

J1mbo Jun 15, 2010 12:53 PM (in response to Steven Bright)

Do the RAID controllers in these new blades have battery-backed write-cache? Although it's perfectly true that the SATA drives are slow in random IOPS terms, the sequential throughput shouldn't be too far off the SAS disks.

http://blog.peacon.co.uk
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4. Re: Poor disk performance - IBM HS22 blades w/ mirrored 500 GB SAS drives

Steven Bright Jun 15, 2010 1:02 PM (in response to J1mbo)

The HS22 does not have a battery backed write cache for the onboard LSI controller. However, a IBM ServerRAID controller option is available that utilizes the CIOv slot and a DIMM slot (for the battery). I believe the option information is:

46C7167 - ServeRAID-MR10ie (CIOv) Controller for IBM BladeCenter
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5. Re: Poor disk performance - IBM HS22 blades w/ mirrored 500 GB SAS drives

J1mbo Jun 15, 2010 2:04 PM (in response to Steven Bright)

Thanks - the omision of the BBWC from the server is the cause of the crap disk performance.

http://blog.peacon.co.uk
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6. Re: Poor disk performance - IBM HS22 blades w/ mirrored 500 GB SAS drives

BigWaveware Aug 31, 2010 3:48 PM (in response to shmick75)

Ideally these Blade Servers really should not be used like standalone servers. They really work best in a shared storage environment like iSCSI or FC SAN. The drive on the server should only be used as a boot drive and o/s share. Hence the slow RPM speed on the larger drive. The IBM Blade server family of servers really isn't designed for the purpose you seek but more as a CPU and RAM resource for your VMware farm. The blade architecture is best utilized where you need fast capacity on demand, scalability and high availability and instant fail-over protection and better control of Vmotion resource allocation.
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