Messages in this thread | | | Date | Wed, 26 Mar 2008 16:21:43 -0700 (PDT) | Subject | Re: larger default page sizes... | From | David Miller <> |
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From: Christoph Lameter <clameter@sgi.com> Date: Wed, 26 Mar 2008 10:56:17 -0700 (PDT)
> One should emphasize that this test was a kernel compile which is not > a load that gains much from larger pages.
Actually, ever since gcc went to a garbage collecting allocator, I've found it to be a TLB thrasher.
It will repeatedly randomly walk over a GC pool of at least 8MB in size, which to fit fully in the TLB with 4K pages reaquires a TLB with 2048 entries assuming gcc touches no other data which is of course a false assumption.
For some compiles this GC pool is more than 100MB in size.
GCC does not fit into any modern TLB using it's base page size.
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