Whole Machine Grinds to a Halt - On Disk Contention.
Posted: Thu Mar 03, 2005 10:31 pm
We are Running:
Datastage Server Version 7.1r1
AIX version 5.2.
Disk is an Hitachi 9500 disk array
connected over Dual Channel a fibre links.
Hello All,
When I run a couple of my Jobs which generate a large amount of Disk IO. This AIX box performs like a dog, ie telnet and issue an ls you may wait up to 2 minutes for a response or try to exit a shell the same sort of wait.
My system administrator and I feel we are getting nowhere and recovering the same ground.
When we use nmon to watch what is happening, the following things are observed:
Once the hard disk reaches 100% (Stating anything from 3000kb to 4000kb per Second Through put) One by one the CPUs show 100% W (Wait). The IO appears to continue to be written, and when it clears the CPUs seem to free up again for a while. Only to repeat the Cycle.
Has anybody seen this before (and hopefully fixed it)????
Thanks Jack
Datastage Server Version 7.1r1
AIX version 5.2.
Disk is an Hitachi 9500 disk array
connected over Dual Channel a fibre links.
Hello All,
When I run a couple of my Jobs which generate a large amount of Disk IO. This AIX box performs like a dog, ie telnet and issue an ls you may wait up to 2 minutes for a response or try to exit a shell the same sort of wait.
My system administrator and I feel we are getting nowhere and recovering the same ground.
When we use nmon to watch what is happening, the following things are observed:
Once the hard disk reaches 100% (Stating anything from 3000kb to 4000kb per Second Through put) One by one the CPUs show 100% W (Wait). The IO appears to continue to be written, and when it clears the CPUs seem to free up again for a while. Only to repeat the Cycle.
Has anybody seen this before (and hopefully fixed it)????
Thanks Jack