PING: Linux: Support transparent hugepages
igor.veresov at oracle.com
Fri Apr 1 11:24:14 PDT 2011
Why is alignment required? Afaik it's perfectly fine to have mixed page
sizes in a single segment. Also, if use use +UseLargePages, all the heap
and generation sizes will be largepage-alinged anyway. Also, some things
like the NUMA-allocator will work better is they know kind of pages the
underlying segment has.
What I would've done is put some logic to distinguish kernels that
support transparent large pages and instead of using all the SHM stuff
just use a mmap + madvise(MADV_HUGEPAGE). On Solaris we do kind of the
same thing, but there you have to do mmap + memcntl(MC_HAT_ADVISE).
Although Solaris 10 also supports out-of-the-box large pages, so in
theory you don't have to do anything, but I guess it's always better to
hint the OS that you really want it.
On 4/1/11 9:31 AM, Andrew Haley wrote:
> Hi all,
> A little while ago I posted this question about adding support for
> Linux's transparent hugepages to HotSpot. I'd really appreciate comments.
More information about the hotspot-dev