Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

AutoLoadPlugin doesn't play well with aggregation plugin #535

Closed
faxm0dem opened this issue Feb 5, 2014 · 4 comments
Closed

AutoLoadPlugin doesn't play well with aggregation plugin #535

faxm0dem opened this issue Feb 5, 2014 · 4 comments

Comments

@faxm0dem
Copy link
Contributor

faxm0dem commented Feb 5, 2014

The config below yields the following error message in the log:

plugin_value_list_clone: Unable to determine interval from context for value list "global/aggregation-num/memory". This indicates a broken plugin. Please report this problem to the collectd mailing list or at <http://collectd.org/bugs/>.
#
AutoLoadPlugin true
Interval 2
TimeOut  2

<LoadPlugin memory>
  Interval 2
</LoadPlugin>

<Plugin aggregation>
  <Aggregation>
    Type memory
    CalculateNum true
  </Aggregation>
</Plugin>

Moreover, when specifying aggregation's LoadPlugin explicitly, one sometimes gets the following:

uc_update: Value too old:

Rerunning sometimes makes it go away, sometimes not. It's quite unpredictable.

Last but not least, the actual value returned by aggregation (should be equal to 4 in theory) is quite unpredictable too: sometimes 0, sometimes 4, sometimes 8. Worse, if the interval of aggregation is N times larger than the interval of memory, the resulting num is 4N.

Am I doing something obvious very wrong?

@tokkee
Copy link
Member

tokkee commented Feb 8, 2014

The former issue is fixed in PR #539

I haven't looked into the aggregation plugin though.

@mfournier
Copy link

Closing since both these problems have independent issues opened (#539 and #297). Feel free to reopen if I misunderstood what you were talking about above !

@tokkee
Copy link
Member

tokkee commented Jul 27, 2014

I think this should be kept open. #539 is a PR addressing parts of this issue and #297 is a separate issue. Anyway, that said, I've looked further into the "value too old" issue. It turns out that it's a race during setup of the plugin (or rather in utils_vl_lookup). However, that should happen independent on whether the autoloading is enabled (but given that it's a race, different configs may make it more or less likely to happen). I'll send a separate PR in a bit.

@tokkee tokkee reopened this Jul 27, 2014
tokkee added a commit to tokkee/collectd that referenced this issue Jul 27, 2014
This could cause multiple aggregation instances to be created in the
aggregation plugin when first writing data to the plugin. This, in turn, led
to "value too old" warnings because subsequently all data was submitted twice.

Thanks to @faxm0dem for reporting this in GH collectd#535.
@mfournier
Copy link

Closing as #539 was superseded by f596915, and the race issue was fixed by #676. The only issue left is #297.

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
None yet
Projects
None yet
Development

No branches or pull requests

3 participants