Troubleshooting
Problem
If the read ahead value (j2_maxPageReadAhead) is the same as the number of buffers for the device (j2_nBufferPerPagerDevice) this makes it possible for the read ahead mechanism to use up all the buffers, which creates a deadlock with all threads waiting on IO
Environment
IBM Smart Analytics System
Resolving The Problem
Keep the value of j2_maxPageReadAhead to less than the value of j2_nBufferPerPagerDevice .
The default tuning advice is for j2_maxPageReadAhead to be half of the value of j2_nBufferPerPagerDevice .
You can use the following command to tune the value of j2_maxPageReadAhead
ioo -o j2_maxPageReadAhead=value
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Document Information
Modified date:
15 September 2021
UID
swg21640392