Short VM freeze when migrating to another host
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@nikade
in VM (linux) with a free i see 94 gb of total memory -
@nikade thanks for the ideas of where to look!
In my case we're testing and just have a 1Gb link between these hosts, which is what I was putting it down to.
This particular VM is a freshly migrated PV from Debian Xen with:
Memory limits (min/max)
Static: 16 MiB/16 GiB
Dynamic: 8 GiB/16 GiBCould that Dynamic setting be the problem because as I recall it reduces the VM to 8 on migrate, so when doing the migrate perhaps 8 isn't enough for the VM?
I will try changing it to 16/16 and see if that has any noticeable impact. Thanks!
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Yes that's very likely.
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@andrewperry yeah try set it 16/16Gb instead, it will probably do some magic
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@olivierlambert hi, today i've upgraded my host..
The big VM frozen for ~7 minutes, is a big vm (96 gbram and 32 cpu) but 7 minutes is a very long time (for customer!)
i've setting 96/06 in dynamic: is a normal time? -
Can you provide more details? 96/96 in dynamic? Just doing live migration or suspending the VM?
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@olivierlambert live migration, the vm is very important (today, in christmas holyday, i've received some phone calls for 7 minutes of freeze..)
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The topology looks insane Also, a live migration shouldn't make the VM inaccessible for more than few seconds, except if there is a LOT of memory pages changes, at a pace that is close to the transfer speed.
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@olivierlambert ops.. why the best topology?
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IIRC, just remove it (small cross) so it should use something default