Synchronisation priority

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robnicholson
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Joined: Thu Apr 14, 2011 3:12 pm

Mon Aug 11, 2014 5:25 pm

Quick question over the attached dialog. Does this priority only control initial synchronisation when a HA node is created/has to be re-synced (e.g. after failure or downtime) or is it always applicable? What exactly are "client requests"? My understanding of HA (plus linked in with other thread over HA performance) is that the sync network when in normal production/use should be as fast as possible otherwise performance degrades, i.e. there should be no throttling of the sync network. So I assume/hope this dialog only applies to initial sync and that it runs as fast as it jolly well can when in normal operation.

But a lot of guesses there.

Cheer, Rob.
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Anatoly (staff)
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Thu Aug 14, 2014 8:48 am

Quick question over the attached dialog. Does this priority only control initial synchronisation when a HA node is created/has to be re-synced (e.g. after failure or downtime) or is it always applicable?
It is always applicable.
What exactly are "client requests"?
It is processing of the IOs that comes from applications that are using StarWind.
My understanding of HA (plus linked in with other thread over HA performance) is that the sync network when in normal production/use should be as fast as possible otherwise performance degrades, i.e. there should be no throttling of the sync network. So I assume/hope this dialog only applies to initial sync and that it runs as fast as it jolly well can when in normal operation.
Agree, but sometimes the system is not too balanced, and synchronization workload makes the client apps to behave slowly, and that is wh we need this feature.
Best regards,
Anatoly Vilchinsky
Global Engineering and Support Manager
www.starwind.com
av@starwind.com
robnicholson
Posts: 359
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Thu Aug 14, 2014 7:42 pm

It is always applicable.
So sync traffic is always throttled? That seems a rather strange thing to do as it's artificially putting a bottleneck in.

Cheers, Rob.
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Anatoly (staff)
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Wed Aug 20, 2014 9:29 am

I`m not sure if understand your question correctly. Could you please clarify?
Best regards,
Anatoly Vilchinsky
Global Engineering and Support Manager
www.starwind.com
av@starwind.com
robnicholson
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Joined: Thu Apr 14, 2011 3:12 pm

Fri Aug 22, 2014 4:04 pm

Above you said that sync priority is always enabled and given the fastest setting still has some component of throttling, then the sync channel always has some form of throttling - so you'll never use the full throughput of 10GbE sync networks. Which I can't quite believe.

Cheers, Rob.
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Anatoly (staff)
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Thu Aug 28, 2014 12:53 pm

I think we`ve got some misunderstanding here. If the priority is set to Synchronization then it is gonna be the process with the highest priority for StarWind, thus allows to fully utilize 10Gbps data link
Best regards,
Anatoly Vilchinsky
Global Engineering and Support Manager
www.starwind.com
av@starwind.com
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