Re: poor (?) perf on NT

From: Stephen_Murray@agsea.com > >I am running a batch process on INFORMIX 7.31TC2 running on NT4.0 >Enterprise SP5 and IBM NetFinity >with 4 CPU and 4G RAM. This same process (called batch1) used to run on a >2-CPU no-name-brand system. >The run time on both systems is 2 hours 5 minutes. The IBM system was >supposed to be faster, but not so. >We had diagnostic gurus look at the IBM to find why it is no faster than a >vanilla system, but they found >no performance or bottleneck issues in memory, CPU, or disk i/o. I >suspected disk i/o so I created a 2nd >instance on the SAME IBM using the SAME disk raid and ran a different batch > process on the new instance >concurrently with batch1 running on the original instance. The batch1 >process completed in 2 hours 7 minutes >with the 2nd instance running batch processing concurrently, which seems to > negate my theory that disk i/o is an >issue. The same data is used on EVERY batch1 run. We set up a dataset, >ran an ontape -s -L 0 to disk, and do a >restore prior to each successive test run. The space utilization for the >instance is about 8G. The batch1 process >is running on a NON-LOGGING database. NT performance monitor shows about >25% overall CPU usage with >batch1 running alone and about 60% overall CPU usage with batch1 running >concurrently with the second >instance doing batch processing. Below are outputs from some onstat >commands representing the activity of >batch1 running concurrently with the second instance running a batch >process on the same system IBM. >Following the onstats is the ONCONFIG file for the batch1 instance and the >online log for time batch1 ran. > >My questions are: > >1) Based on the chunk writes from onstat -F (201053) and the total page >writes from onstat -p (427893), the average > chunk write is only 2 pages. I have seen over 6 pages per write on >my unix systems. Is 2 pages per chunk write > too low? If so, what can be done? > >2) The onstat -g ioq shows max queue length for the 3 kaio threads to be >52, 33, and 33. I have heard the max queue > length for kaio should be no more than 32. Are mine too high? If >so, what can be done? > >3) For the onstat -g iov output: > a) are the io/s values acceptable for the kaio threads? > b) are the # of wakeups too high (over 300,000,000 total for the 3 >kaio threads) ? > >4) For the onstat -g glo output: > a) what are "lngspins" and is the value 21 acceptable? > b) what are the "yield 0", "yield n", and "yield forever" and are >the > values listed acceptable? > >5) Another comments or feedback would be appreciated UPDATE STATISTICS? I've also run into performance hassles on NT with 7.31 (but I seem to be alone) However, 7.30 runs lickety-split. Are you using PDQ? Is your data fragmented? Is this actually a batch routine, or does it do zillions of small ops? ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com