Better stream performance when transparent hugepages are on

Question

On rhel 7, when transparent hugepages are activated, I get a better stream benchmark performance than when transparent hugepages are off.

Do you have any idea of a kernel parameter (or another thing) which could trigger this behavior ?

I was expecting to have same stream performance with or without transparent hugepages (like in rhel 6) (or only a small difference). The performance difference is around 10GB/s.

score 1 · Answer 1 · answered Nov 27 '16 at 00:04

1

Transparent hugepages are the thing that is causing this performance increase. The kernel in Cent 6 and Cent 7 are different by quite a lot. THP can optimize large contiguous memory patterns, and greatly help the system to avoid hitting the Translation Lookaside Buffer as often.

Memory management in Cent 7 is vastly different than in Cent 6, in the direction of improvement.

answered Nov 27 '16 at 00:04

Spooler

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Thanks for the answer, would you have some links to get more infos about the differences or the new memory management mechanisms ? – Nov 27 '16 at 16:13

Better stream performance when transparent hugepages are on

1 Answers1