Chegu Vinod <address@hidden> wrote:
On 4/30/2013 8:20 AM, Juan Quintela wrote:
(qemu) info migrate
capabilities: xbzrle: off auto-converge: off <----
Migration status: active
total time: 1487503 milliseconds
148 seconds
1487 seconds and still the Migration is not completed.
expected downtime: 519 milliseconds
transferred ram: 383749347 kbytes
remaining ram: 2753372 kbytes
total ram: 268444224 kbytes
duplicate: 65461532 pages
skipped: 64901568 pages
normal: 95750218 pages
normal bytes: 383000872 kbytes
dirty pages rate: 67551 pages
---
(qemu) info migrate
capabilities: xbzrle: off auto-converge: on <----
Migration status: completed
total time: 241161 milliseconds
downtime: 6373 milliseconds
6.3 seconds and finished, not bad at all O:-)
That's the *downtime*.. The total time for migration to complete is
241 secs. (SpecJBB is
one of those workloads that dirties memory quite a bit).
Sorry, you are right. Imressive anyways for such small change.
+/* To reduce the dirty rate explicitly disallow the VCPUs from spending
+ much time in the VM. The migration thread will try to catchup.
+ Workload will experience a greater performance drop but for a shorter
+ duration.
+*/
+void *migration_throttle_down(void *opaque)
+{
+ throttling = true;
+ while (throttling_needed()) {
+ CPUArchState *penv = first_cpu;
I am not sure that we can follow the list without the iothread lock
here.
Hmm.. Is this due to vcpu hot plug that might happen at the time of
live migration (or) due
to something else ? I was trying to avoid holding the iothread lock
for longer duration and slow
down the migration thread...
Well, thinking back about it, what we should do is disable cpu
hotplug/unplug during migration