ChrisPaulson
Member
Our company has had a problem on a customer’s site. The site has been complaining about very poor system performance.
The site (details don’t matter that much in this question):
F50 dual processor
AIX 4.2.1
0.75 gig memory
5 SSA disks
100mb network card
I started looking at site and started trying to tune the DB (being quite sure about the software as its on lots of other sites and running okay).
On initial investigation the vmstat was showing very poor I/O wait times around 60 – 90 percent.
To cut a long story short we discovered hardware fault. The fault was causing the switch the server was connected to, to go very slow.
When the problem with the switch was resolved and the system was brought back the I/O wait time went down to around 20 – 40 percent.
I can only conclude from this that I/O wait time on vmstat is including network wait time as well.
Can anyone confirm this?
The site (details don’t matter that much in this question):
F50 dual processor
AIX 4.2.1
0.75 gig memory
5 SSA disks
100mb network card
I started looking at site and started trying to tune the DB (being quite sure about the software as its on lots of other sites and running okay).
On initial investigation the vmstat was showing very poor I/O wait times around 60 – 90 percent.
To cut a long story short we discovered hardware fault. The fault was causing the switch the server was connected to, to go very slow.
When the problem with the switch was resolved and the system was brought back the I/O wait time went down to around 20 – 40 percent.
I can only conclude from this that I/O wait time on vmstat is including network wait time as well.
Can anyone confirm this?