515a01279a
Currently x86's kvm_vm_ioctl_get_dirty_log() needs to allocate a bitmap by vmalloc() which will be used in the next logging and this has been causing bad effect to VGA and live-migration: vmalloc() consumes extra systime, triggers tlb flush, etc. This patch resolves this issue by pre-allocating one more bitmap and switching between two bitmaps during dirty logging. Performance improvement: I measured performance for the case of VGA update by trace-cmd. The result was 1.5 times faster than the original one. In the case of live migration, the improvement ratio depends on the workload and the guest memory size. In general, the larger the memory size is the more benefits we get. Note: This does not change other architectures's logic but the allocation size becomes twice. This will increase the actual memory consumption only when the new size changes the number of pages allocated by vmalloc(). Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> |
||
|---|---|---|
| .. | ||
| assigned-dev.c | ||
| async_pf.c | ||
| async_pf.h | ||
| coalesced_mmio.c | ||
| coalesced_mmio.h | ||
| eventfd.c | ||
| ioapic.c | ||
| ioapic.h | ||
| iodev.h | ||
| iommu.c | ||
| irq_comm.c | ||
| Kconfig | ||
| kvm_main.c | ||