[pdm-devel] [PATCH proxmox-datacenter-manager v6 00/23] metric collection improvements (concurrency, API, CLI)

[Lukas Wagner]

On Thu Aug 21, 2025 at 2:53 PM CEST, Dominik Csapak wrote:
> just a first high level question while i'm testing/reviewing this:
>
> when using this patch, it seems the collection interval is much reduced?
>
> e.g. in the gui I'm missing up to the last 10 minutes now?
> (at 14:49 the last point i have for the rrd is from 14:40)
>
> is this by design? i get that we don't want to pull too often,
> but showing up to 10minutes out of date graphs is also not practical?

Maybe I misremember, but I vaguely recall Thomas and Dietmar
independently mentioning that the default metric polling interval should
be higher than what is implemented right now (1min).

Anyway, at some point the interval should be configurable (already was
in earlier versions of this series, but I dropped these patches for now
since it's not 100% clear yet to me *where* we want to configure these
things/store the settings). So then the question is what *default* to
use - for now I settled for 10mins. But I'm open for better values, I
don't have hard feelings about this.

>
> my naive solution would be to proxy the rrd requests to the
> pve nodes directly, but then why would we need the metric
> collection in the first place?

We also could trigger an out-of-schedule metric collection for a remote
when the RRD graph calls the rrddata endpoint (the functions for
triggering the collection of a single remote are already there, albeit
non-blocking, so this would need some changes). Fetching the missing
data for a single remote should be fast enough any way. The rrddata
endpoint could have some timeout for waiting for the results of
collecting that single remote; if that one is exceeded we don't wait
until the collection results are done but simply return the existing
data.

>
> i guess i'm just missing something here, maybe you can point it out for me?