Hi, Mark -
> >Please see git://sourceware.org/git/pcp.git branch fche/json for this
> >ditty:
> ----------^^^^^ pcpfans.git
Yes, sorry.
> the patch itself looks ok to me, but as I read it, this is not just
> an err handling issue - if the cache has stale entries then that
> suggests the root cause of this issue is in the refresh
> functionality - shouldn't it invalidate all entries and then
> re-activate only those still current (plus any new instances)?
Correcting that latent bug (if it is one) is likely possible as a
follow-on. In the present case, a dynamic data source could have
wildly fluctuating sets of instances available from fetch to fetch
(e.g., snapshots of recent traffic between source-host network-address
pairs, where A-B traffic might appear then disappear then later
reappear). What pmdaCacheOp sequence would you recommend?
> Also, some qa to demonstrate the issue and the fix would be
> appropriate, especially at this stage of the release.
The problem showed up with dramatic slowdowns and lots of diagnostic
I/O traffic into /var/tmp and the pmda .log file, not as differences
at the pmapi client level (other than sloth). How would one qa that?
- FChE
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