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| author | Fam Zheng <famz@redhat.com> | 2016-03-01 14:18:24 +0800 |
|---|---|---|
| committer | Timothy Pearson <tpearson@raptorengineering.com> | 2019-11-29 19:49:12 -0600 |
| commit | b527bb9200ccaaf0afcc83c13a34ee7bf2d28438 (patch) | |
| tree | 2285e7770378832466798031b167e6f4c73c0528 /cpus.c | |
| parent | 74f8e4eb79703798d61775c6b3df40ba700b5916 (diff) | |
| download | hqemu-b527bb9200ccaaf0afcc83c13a34ee7bf2d28438.zip hqemu-b527bb9200ccaaf0afcc83c13a34ee7bf2d28438.tar.gz | |
exec: Introduce AddressSpaceDispatch.mru_section
Under heavy workloads the lookup will likely end up with the same
MemoryRegionSection from last time. Using a pointer to cache the result,
like ram_list.mru_block, significantly reduces cost of
address_space_translate.
During address space topology update, as->dispatch will be reallocated
so the pointer is invalidated automatically.
Perf reports a visible drop on the cpu usage, because phys_page_find is
not called. Before:
2.35% qemu-system-x86_64 [.] phys_page_find
0.97% qemu-system-x86_64 [.] address_space_translate_internal
0.95% qemu-system-x86_64 [.] address_space_translate
0.55% qemu-system-x86_64 [.] address_space_lookup_region
After:
0.97% qemu-system-x86_64 [.] address_space_translate_internal
0.97% qemu-system-x86_64 [.] address_space_lookup_region
0.84% qemu-system-x86_64 [.] address_space_translate
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <1456813104-25902-8-git-send-email-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'cpus.c')
0 files changed, 0 insertions, 0 deletions
