OK, I admit it does not make sense to limit the pool from 5 to 3 as that would not make big difference. I guess those threads should not have large impact on resources usage anyway. It just looks slightly suspicious in Java VisualVM, where you can see five parked threads most of the time while other components go with a thread or two. Now I know why.
Thanks for your insight. Milan po 23. 3. 2020 v 14:23 odesílatel Brian Brazil < [email protected]> napsal: > On Mon, 23 Mar 2020 at 13:03, Milano Nicolum <[email protected]> wrote: > >> Maybe I wasn't clear. I want the pool smaller. If there is only one >> Prometheus instance scraping it every 15 seconds or so, I don't think 5 >> threads are needed all the time. >> > > Threads are pretty cheap, and the minimum safe number is around 3 so with > that small a range I don't see a need for it to be configurable. > > If your resource constraints are that tight, you probably need a custom > server. > > Brian > > >> >> Milan >> >> po 23. 3. 2020 v 14:00 odesílatel Brian Brazil < >> [email protected]> napsal: >> >>> On Mon, 23 Mar 2020 at 12:49, Milano Nicolum <[email protected]> wrote: >>> >>>> So it would be possible to make a PR to make that value/Executorservice >>>> configurable? >>>> >>> >>> Why do you need it to be bigger? >>> >>> If you've more nice needed, you're probably best providing your own http >>> server. That one is only meant to get you up and running quickly. >>> >>> Brian >>> >>> >>>> >>>> Milan >>>> >>>> po 23. 3. 2020 v 13:40 odesílatel Brian Brazil < >>>> [email protected]> napsal: >>>> >>>>> On Mon, 23 Mar 2020 at 12:38, Milano Nicolum <[email protected]> >>>>> wrote: >>>>> >>>>>> Hi, >>>>>> at the moment I use prometheus-java-client 0.8.1 with out of the box >>>>>> HTTPServer to expose metrics on my K8S pods and Prometheus discovery to >>>>>> scrape them. >>>>>> I just wonder if there is any particular reason to use >>>>>> fixedThreadPool of size 5 as default. - >>>>>> https://github.com/prometheus/client_java/blob/master/simpleclient_httpserver/src/main/java/io/prometheus/client/exporter/HTTPServer.java#L167 >>>>>> >>>>> >>>>> It's a hardcoded value, and it seems unlikely that you'd have 5 >>>>> scrapes at once so it's a conservative choice. >>>>> >>>>> Brian >>>>> >>>>> >>>>>> >>>>>> >>>>>> As the metrics endpoint is usually accessed by prometheus scrape only >>>>>> I feel as 5 threads are quite a luxury to have on every pod. I wonder if >>>>>> there is any response time based reasoning behind the pool size or some >>>>>> situation I still have to experience. >>>>>> >>>>>> https://github.com/prometheus/client_java/blob/master/simpleclient_httpserver/src/main/java/io/prometheus/client/exporter/HTTPServer.java#L167 >>>>>> >>>>>> While I guess the default HTTPServer could be replace by different >>>>>> implementation I just want to know what setup is the most lightweight and >>>>>> reliable at the same time. >>>>>> Thanks, >>>>>> Milan. >>>>>> >>>>>> -- >>>>>> You received this message because you are subscribed to the Google >>>>>> Groups "Prometheus Users" group. >>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>> send an email to [email protected]. >>>>>> To view this discussion on the web visit >>>>>> https://groups.google.com/d/msgid/prometheus-users/9e57f6c6-51ad-49c0-8c9a-b3f58945143a%40googlegroups.com >>>>>> <https://groups.google.com/d/msgid/prometheus-users/9e57f6c6-51ad-49c0-8c9a-b3f58945143a%40googlegroups.com?utm_medium=email&utm_source=footer> >>>>>> . >>>>>> >>>>> >>>>> >>>>> -- >>>>> Brian Brazil >>>>> www.robustperception.io >>>>> >>>> >>> >>> -- >>> Brian Brazil >>> www.robustperception.io >>> >> -- >> You received this message because you are subscribed to the Google Groups >> "Prometheus Users" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/prometheus-users/CAEDfKrop8HnRMBOGRX-9Zm_wR--HZNZ2kXB56vAE8hPpD000AA%40mail.gmail.com >> <https://groups.google.com/d/msgid/prometheus-users/CAEDfKrop8HnRMBOGRX-9Zm_wR--HZNZ2kXB56vAE8hPpD000AA%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . >> > > > -- > Brian Brazil > www.robustperception.io > -- You received this message because you are subscribed to the Google Groups "Prometheus Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/prometheus-users/CAEDfKroO2Z0f2uzO1G-FBPdcSXK%3Dx8erCGAqWFNAK3cwj8tuVw%40mail.gmail.com.
