On Thu, May 2, 2013 at 3:33 PM, Frank Peters <frank.pet...@comcast.net> wrote: > During kernel configuration there is an option called > CONFIG_TRANSPARENT_HUGEPAGE > which allows the use of Transparent Hugepages or application memory pages > larger > than the traditional 4K size. This option has been available for a while but > I've never enabled it. However, it would seem like a good idea to use. > > Searching for more information I can find no comments on actual Hugepage > performance for a simple desktop Linux system. Can anyone verify or refute > the idea that Transparent Hugepages will lead to improvements on a desktop > system? Does an application have to specifically request Hugepages or > does the allocation occur for all applications?
AFAIR there were claims of up to 10% performance improvement in certain test scenarios, and that you don't need to do anything special to exploit THP in existing software (but applications can be rewritten in such a way as to specifically make better use of it). There is a setting that lets you expose THP _only_ to those programs which specifically request it, rather than backwards-compatible to all programs if you are worried about that. Check out the in-kernel documentation (vm/transhuge.txt) for details. Anecdotal: I have turned it off and on and don't "feel" any difference in the operation of my computer either way...
