Bug #85372 for jmx4perl: Use of uninitialized value $old_value in substruction (-) JMX/Jmx4Perl/Nagios/SingleCheck.pm line 311

Fri May 17 05:15:56 2013 admir [...] trakic.com - Ticket created

Subject:	Use of uninitialized value $old_value in substruction (-) JMX/Jmx4Perl/Nagios/SingleCheck.pm line 311
Date:	Fri, 17 May 2013 11:15:33 +0200
To:	bug-jmx4perl [...] rt.cpan.org
From:	Admir Trakic <admir [...] trakic.com>

perl, v5.10.0 I'm experiencing periodic errors while using check_jmx4perl with --mbean --attribute ---delta args. BTW: is there any way how to do incremental checks on descending values? Thx -- Admir Trakic http://web.trakic.com/

Wed Jun 18 02:01:57 2014 roland [...] cpan.org - Correspondence added

On Fri May 17 05:15:56 2013, admir@trakic.com wrote:
Show quoted text

> perl, v5.10.0
>
> I'm experiencing periodic errors while using check_jmx4perl with --mbean
> --attribute ---delta args.
>
> BTW: is there any way how to do incremental checks on descending values?
>
> Thx
>

Sorry for coming back to you that late.

This warning means, that from time to time you measure an undefined value which is stored in the history. Can you give me the check configuration where this happen to you ?

Setting the old value to 0 in case of 'undefined' doesn't help much, because the relative value will be messed up neverthelesse. Better a warning here to indicate that something is wrong. So I probably wont change this.

You can do of course checks on descending values, the 'velocity' (that's what you are measuring) is then negative. You only have to adopt the threshold according to http://nagiosplug.sourceforge.net/developer-guidelines.html#THRESHOLDFORMAT so that you can check, when the velocity goes *below* a certain value.

Wed Jun 18 02:01:57 2014 The RT System itself - Status changed from 'new' to 'open'