We have two 8400's which have been upgraded from 4.0D to 5.1PK4
The upgrade went OK but on the first machine we were getting an I/O
error when copying a file between file systems. The file was created
(0k) but no data copied, the cp command gave 'I/O ERROR'.
This seemed to happen randomly, copying the same file a second time
sometimes worked.
The problem was 'fixed' by removing 5 patches 653, 494, 232, 230 and
226.
We then upgraded the second machine to the same patch state.
This is used for performance testing our Oracle 8.1.7 application.
The 'benchmark' test was run to confirm all was OK...
But batch jobs now took 2 to 3 times longer to run. Analysis showed
this to be due to Read I/O time from the database, previously <10ms
now about 26ms. Copying large files between file systems also seemed
slower.
Applying the missing patches from PK4 reduced the Read I/O time to
18ms and jobs ran at less than twice the elapsed time of 4.0D
BUT the I/O problem caused jobs which wrote to flat files to fail.
We removed the 5 patches again and changed the kernel parameter
'fifo_do_adaptive = 0' as per a previous summary (Thanks Rob Pieters)
This gave us a 15% improvement in elapsed time but the longer Read I/O
remained (>20ms).
So what do we do next... All ideas gratefully received.
Brian Hunter
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Received on Tue Jan 15 2002 - 14:40:37 NZDT