diff options
| author | Peter Xu <peterx@redhat.com> | 2021-05-06 12:05:47 -0400 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2021-05-26 14:49:45 +0200 |
| commit | 2ea5cb0a47c9dbf78235de30a0d5846a4ab6d995 (patch) | |
| tree | cae70dfaa60a895ad56b19c6af2514537dfb6e0a /qemu-options.hx | |
| parent | 563d32ba9bb92df6170a53826a174e59ae73412f (diff) | |
KVM: Add dirty-ring-size property
Add a parameter for dirty gfn count for dirty rings. If zero, dirty ring is
disabled. Otherwise dirty ring will be enabled with the per-vcpu gfn count as
specified. If dirty ring cannot be enabled due to unsupported kernel or
illegal parameter, it'll fallback to dirty logging.
By default, dirty ring is not enabled (dirty-gfn-count default to 0).
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210506160549.130416-9-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'qemu-options.hx')
| -rw-r--r-- | qemu-options.hx | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/qemu-options.hx b/qemu-options.hx index e22fb94d99..ecdb064409 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -141,6 +141,7 @@ DEF("accel", HAS_ARG, QEMU_OPTION_accel, " kvm-shadow-mem=size of KVM shadow MMU in bytes\n" " split-wx=on|off (enable TCG split w^x mapping)\n" " tb-size=n (TCG translation block cache size)\n" + " dirty-ring-size=n (KVM dirty ring GFN count, default 0)\n" " thread=single|multi (enable multi-threaded TCG)\n", QEMU_ARCH_ALL) SRST ``-accel name[,prop=value[,...]]`` @@ -181,6 +182,17 @@ SRST where both the back-end and front-ends support it and no incompatible TCG features have been enabled (e.g. icount/replay). + + ``dirty-ring-size=n`` + When the KVM accelerator is used, it controls the size of the per-vCPU + dirty page ring buffer (number of entries for each vCPU). It should + be a value that is power of two, and it should be 1024 or bigger (but + still less than the maximum value that the kernel supports). 4096 + could be a good initial value if you have no idea which is the best. + Set this value to 0 to disable the feature. By default, this feature + is disabled (dirty-ring-size=0). When enabled, KVM will instead + record dirty pages in a bitmap. + ERST DEF("smp", HAS_ARG, QEMU_OPTION_smp, |