Re: 3PAR 7200 poor performance
Posted: Tue Jan 14, 2014 5:29 am
"Best IOMETER results for 12 15k FC disks on my 3Par are 350MBps."
"Best IOMETER results for 24 7k NL disks on my 3Par are 170MBps."
"Even in RAID0."
Your results are meaningless without knowing queue depth, I/O size, read / write ratio, random / sequential mix, alignment etc. The fact you are seeing similar results on Raid 0 suggests you aren't pushing the array. If you can post those details then it may be possible for someone to repeat the test on a similar setup maybe with a CPG filter to match your drive layout.
Check the Operating System Implementation Guides here http://goo.gl/mzM4Y7 they list all of the required steps and settings required to connect each O/S type to ensure Host Persona, MPIO, load balancing etc are correct.
If you are using 8Gb switches ensure the fill word is set correctly to 3 on all ports connecting to the 3PAR, this info can be found in the SAN Design & Reference Guide http://goo.gl/Zpkkxg page 103 rule 3.
The array is designed to handle multiple concurrent workloads (multi-tenancy) and to avoid any one workload swamping the others. So if you have a single stream sequential workload and are expecting stellar performance, that's just not what it's optimized for. Ramp up the queue depth or get more workers running in IO Meter and you'll see the performance increase. This is how arrays work in the real world rather than on a artificial benchmark.
Finally if you are still having problems you could try the below to eliminate comms issues, but you'll need to have a repeatable test you can use to validate the results.
If you think you are having retry issues you should try switching all of the 3PAR front end ports to 4Gb using "controlport" also lock the switch ports to 4Gb. It sounds counter intuitive but if you are having undetected comms retries due to cable or transceiver issues, they should reduce and performance will improve. If that's the case log a call with support to investigate / replace the failing component.
"Best IOMETER results for 24 7k NL disks on my 3Par are 170MBps."
"Even in RAID0."
Your results are meaningless without knowing queue depth, I/O size, read / write ratio, random / sequential mix, alignment etc. The fact you are seeing similar results on Raid 0 suggests you aren't pushing the array. If you can post those details then it may be possible for someone to repeat the test on a similar setup maybe with a CPG filter to match your drive layout.
Check the Operating System Implementation Guides here http://goo.gl/mzM4Y7 they list all of the required steps and settings required to connect each O/S type to ensure Host Persona, MPIO, load balancing etc are correct.
If you are using 8Gb switches ensure the fill word is set correctly to 3 on all ports connecting to the 3PAR, this info can be found in the SAN Design & Reference Guide http://goo.gl/Zpkkxg page 103 rule 3.
The array is designed to handle multiple concurrent workloads (multi-tenancy) and to avoid any one workload swamping the others. So if you have a single stream sequential workload and are expecting stellar performance, that's just not what it's optimized for. Ramp up the queue depth or get more workers running in IO Meter and you'll see the performance increase. This is how arrays work in the real world rather than on a artificial benchmark.
Finally if you are still having problems you could try the below to eliminate comms issues, but you'll need to have a repeatable test you can use to validate the results.
If you think you are having retry issues you should try switching all of the 3PAR front end ports to 4Gb using "controlport" also lock the switch ports to 4Gb. It sounds counter intuitive but if you are having undetected comms retries due to cable or transceiver issues, they should reduce and performance will improve. If that's the case log a call with support to investigate / replace the failing component.
update to Inform 3.1.2MU2 (now it is 3.1.3)