Details
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Bug
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Resolution: Incomplete
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Major
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None
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None
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None
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3
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9223372036854775807
Description
On dense cored systems with hyperthreading active, you end up with a lot of execution threads. An example would be a system with 256 total threads.
The libcfs partition code divides those up into 16 partitions of 16 threads each (based on a math algorithm...not logical grouping based on hyperthreading).
Lnet-selftest then creates a group of scheduler threads in each partition equal to the number of execution threads minus 1 (so 15 per partition for our example). That means it creates 240 scheduler threads. This actually reduces performance rather than improves it.
We need to limit the number of lnet-selftest scheduler threads to some reasonable number per partition.
Note: another bug will be created to look at how we group the execution threads into partitions. It needs to make more sense than it does.
