From: Chegu Vinod <chegu_vinod@hp.com>
To: Satoru Moriya <satoru.moriya@hds.com>,
qemu-devel qemu-devel <qemu-devel@nongnu.org>
Subject: Re: [Qemu-devel] [PATCH v4] Add option to mlock qemu and guest memory
Date: Sun, 21 Apr 2013 22:16:26 -0700 [thread overview]
Message-ID: <5174C7AA.5040701@hp.com> (raw)
Hi Satoru,
FYI... I had tried to use this change earlier and it did show some
improvements in perf. (due to reduced exits).
But as expected mlockall () on large sized guests adds a considerable
delay in boot time. For e.g. on an 8 socket Westmere box => a 256G guest
: took an additional ~2+ mins to boot and a 512G guest took an
additional ~5+ mins to boot. This is mainly due to long time spent in
trying to clear all the pages.
77.96% 35728 qemu-system-x86 [kernel.kallsyms] [k]
clear_page_c
|
--- clear_page_c
hugetlb_no_page
hugetlb_fault
follow_hugetlb_page
__get_user_pages
__mlock_vma_pages_range
__mm_populate
vm_mmap_pgoff
sys_mmap_pgoff
sys_mmap
system_call
__GI___mmap64
qemu_ram_alloc_from_ptr
qemu_ram_alloc
memory_region_init_ram
pc_memory_init
pc_init1
pc_init_pci
main
__libc_start_main
Need to have a faster way to clear pages.
Vinod
next reply other threads:[~2013-04-22 5:16 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-04-22 5:16 Chegu Vinod [this message]
2013-04-23 3:47 ` [Qemu-devel] [PATCH v4] Add option to mlock qemu and guest memory Satoru Moriya
-- strict thread matches above, loose matches on Subject: below --
2013-03-26 15:05 Satoru Moriya
2013-03-27 15:18 ` Anthony Liguori
2013-03-28 4:43 ` Satoru Moriya
2013-04-02 15:03 ` Seiji Aguchi
2013-04-02 19:12 ` Anthony Liguori
2013-04-03 7:57 ` Markus Armbruster
2013-04-22 18:38 ` Anthony Liguori
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