Re: [PATCH -V2 -mm 0/4] mm, huge page: Copy target sub-page last when copy huge page

2018-05-25 Thread Christopher Lameter
On Thu, 24 May 2018, Huang, Ying wrote: > If the cache contention is heavy when copying the huge page, and we > copy the huge page from the begin to the end, it is possible that the > begin of huge page is evicted from the cache after we finishing > copying the end of the huge page. And it is pos

[PATCH -V2 -mm 0/4] mm, huge page: Copy target sub-page last when copy huge page

2018-05-23 Thread Huang, Ying
From: Huang Ying Huge page helps to reduce TLB miss rate, but it has higher cache footprint, sometimes this may cause some issue. For example, when copying huge page on x86_64 platform, the cache footprint is 4M. But on a Xeon E5 v3 2699 CPU, there are 18 cores, 36 threads, and only 45M LLC (la