On Thu, Mar 23, 2017 at 07:01:48PM -0400, Pavel Tatashin wrote: > When deferred struct page initialization feature is enabled, we get a > performance gain of initializing vmemmap in parallel after other CPUs are > started. However, we still zero the memory for vmemmap using one boot CPU. > This patch-set fixes the memset-zeroing limitation by deferring it as well. > > Here is example performance gain on SPARC with 32T: > base > https://hastebin.com/ozanelatat.go > > fix > https://hastebin.com/utonawukof.go > > As you can see without the fix it takes: 97.89s to boot > With the fix it takes: 46.91 to boot. How long does it take if we just don't zero this memory at all? We seem to be initialising most of struct page in __init_single_page(), so it seems like a lot of additional complexity to conditionally zero the rest of struct page. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
