Add Diffusion to third-party software list.

[philipa]

@brian-brazil

Diffusion is a commercial software product from Push Technology.

[brian-brazil]

That URL isn't right, and I think https://developers.pushtechnology.com/hc/en-us/articles/360034215494-How-To-Use-Metric-Collectors would be more useful.

You don't appear to actually document how to get the metrics. I presume "gateway" doesn't mean the pushgateway, I can imagine that confusing some of your users so would suggest clarifying.

[philipa]

Thanks Brian; yes I agree. The blog you found is about general configuration of Diffusion's metric collection and not specific to Prometheus.

I've updated the URL to point to the relevant page in our manual.

[brian-brazil]

Thanks!

diffusion_sessions_peak sounds like a gauge rather than a counter. Counters should also generally end in _total (except if part of a Summary/Histogram), and _count should be for that series in a Summary/Histogram.

[philipa]

diffusion_sessions_peak can only go up. It is the highest number of sessions the server has ever hosted (it is the maximum value of diffusion_sessions_open). There is a separate diffusion_sessions_total metric

[brian-brazil]

That's still a Gauge. You care about the absolute value, not how fast it is going up.

[philipa]

Since _peak is monotonically increasing, isn't a counter appropriate? What benefit would using a gauge bring?

[brian-brazil]

Counters always go up, but that doesn't mean that everything that always goes up is a counter. Counters are not meant to be usable without using rate() first, whereas diffusion_sessions_peak is usable as-is.

[SuperQ]

@philipa Even tho it's monotonically increasing, it's not counting anything.

[philipa]

OK, schooled! I'll get this fixed. Thanks for your patience.