[Info-vax] NetBackup Performance Woes

[Geek Nerdly]

It's very consistent:

Queue Length spikes to as high as 50 and does not dip below 3 on node B (where backup runs) while backup is running, where at the same time on node A Queue Length hovers between 0 & 1.  Response Time tracks with, but varies more on its scale.

Lock conversations spike (on both nodes) while backup is running.

Interrupt Mode barely occurs at any other time of the day on either system, and it's nuts on node B while backup is running.

Processes in MWAIT states really only occur while backup is running, mostly on node be but there is the occasional occurence on node A.

Cache Read Bypasses (which I'd expect to happen during a backup) are sustained at high levels on node B only during backup, they have the occasional quick spike on node A when processing is heavy (and it's to be expected there and when I see them).

I suppose it could be as silly as a faulty HBA on node B, but we've got a similar job running on an isolated node (not on the cluster, but connected to the same SAN with a different pool of disk) and we're seeing similar behavior.

I've asked the folks who manage the storage if they can provide load/utilization data so I can tie any of it together with the T4 data I have.

More and more I am thinking LIMIT_BANDWIDTH may sort this out.  I'll have to try it and see what it does.  I will post results here.

Thank you for your time and attention!

On Wednesday, May 20, 2015 at 10:22:51 AM UTC-4, Geek Nerdly wrote:
> Have experienced severe resource consumption by NetBackup release 7.5.  This problem can bring a node to its knees, and that at times affects the whole cluster.
> 
> Symantec provides no guidelines for tuning process quotas for their backup agent to balance throughput vs. resource consumption.  Their documentation only states that there are process quotas and they can be tuned.  Their support is lacking knowledge, experience (with OpenVMS at least) or interest in being of useful assistance.
> 
> Does anyone out there have any experience or guidelines for approaching this problem specifically with NetBackup?  
> 
> Many thanks in advance.