Trigger using perf_counter

[pontus]

I have an item defined as
perf_counter[\Process(fmscwpc)\Thread Count]
and a trigger defined as
last(/host.domain/perf_counter[\Process(fmscwpc)\Thread Count])=0

For some reason this does not trigger a problem when the agent can't get any perf counter as ZBX_NOTSUPPORTED: Cannot obtain performance information from collector.

Shouldn't this trigger a problem?I have an item defined as

[ISiroshtan]

No, it should not. The last() function evaluates data, when item switches into unsupported state it does not generate any new values -> trigger would not be reevaluated -> trigger will not fire.

You would want to use nodata() function instead. It will fire if no new values for item received for X amount of time. Set it like

nodata(/host.domain/perf_counter[\Process(fmscwpc)\Thread Count], X)=1

, where X is double or triple or the collection time of item or more (so if item collets every 60 seconds, set X to 120 at least, meaning item failed at least two consecutive checks and it's not just a restart of service or some other brief hiccup)
You can set it as alternative condition to existing one, so something like

last(/host.domain/perf_counter[\Process(fmscwpc)\Thread Count])=0 or nodata(/host.domain/perf_counter[\Process(fmscwpc)\Thread Count], 5m)=1

[cyber]

Or add preprocessing "check for not supported value", Custom on fail -> set value to 0. In that case, item will not tuirn to not supported and your trigger will work also.