Review request: (turn off transparent huge pages) 8024838: Significant slowdown due to transparent huge pages

[Andrew Hughes]

----- Original Message -----
> Please review this change to turn off transparent huge pages by default.
> 
> http://cr.openjdk.java.net/~stefank/8024838/webrev.00/
> 
> 8024838: Significant slowdown due to transparent huge pages
> Summary: Don't turn on transparent huge pages
> (-XX:+UseTransparentHugePages) unless explicitly specified on the
> command line. This has the effect that large pages are never turned on
> Linux unless the user has explicitly enabled any of the large pages
> flags: -XX:+UseLargePages, -XX:+UseTransparentHugePages,
> -XX:+UseHugeTLBFS, and -XX:+UseSHM.
> Reviewed-by: TBD1, TBD2
> 
> thanks,
> StefanK
> 

Can you explain where you see this slowdown?  I'm a little worried that
this does not seem to have been questioned in this review.

Thanks,
-- 
Andrew :)

Free Java Software Engineer
Red Hat, Inc. (http://www.redhat.com)

PGP Key: 248BDC07 (https://keys.indymedia.org/)
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