NA SM: performance lowers when buffer size increases

[soumagne]

When doing bulk transfers using the shared-memory plugin and process_vm_readv/writev calls, performance diminishes as the size of the data increases.

[scottatchley]

On Nov 9, 2017, at 3:09 PM, Jerome Soumagne [email protected] wrote:

When doing bulk transfers using the shared-memory plugin and process_vm_readv/writev calls, performance diminishes as the size of the data increases.

Is the performance decrease linear with message size or are there decreases at specific size? Is this related to cache sizes?

[soumagne]

Hi Scott, I need to investigate some more but yes it seems to happen after a specific size. I need to do some more comparisons to see if this is related to the last level cache or to some kernel limitations...