On 2008-07-18T16:46:49, Dejan Muhamedagic <[EMAIL PROTECTED]> wrote:
> We are talking about different metrics. All monitor operations
> require a fork of a shell.
... which incidentially is also something we eventually need to fix, and
either fork a daemon when the RA starts (which then would talk to the
LRM directly), or have a "monitor-loop" extension which keeps running
and simply writes "ok" every so often to stdout or "failed" when it's
gone down.
We really need to avoid forking completely.
> And that probably more than once. The leaner the shell the better the
> performance. It also looks like, though I'm not entirely happy with
> that, that people tend to use more rather than less monitors and to
> schedule them very frequently (once a second? anybody?).
Well, obviously, they want them to detect failures quickly; no other
way.
The shell scripts then also call out to many scripts and binaries
anyway, so whether or not bash gets forked really doesn't matter.
While I see your point, but I'd much rather have a RA written in bash
than none at all for some service, and the submitter gets to chose the
language (or shell).
> And, unfortunately, a better monitor API/interface is still far away
> for most resource types.
It's trivial once someone did it ;-)
Anyway, this discussion is already going on for longer than its worth,
and I apologize for starting it. My fault, but it proves the bikeshed
doctrine ;-)
Regards,
Lars
--
Teamlead Kernel, SuSE Labs, Research and Development
SUSE LINUX Products GmbH, GF: Markus Rex, HRB 16746 (AG Nürnberg)
"Experience is the name everyone gives to their mistakes." -- Oscar Wilde
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