[sysmon-help] Maxqueued at Sysmon

Jared Mauch jared at puck.nether.net
Fri Mar 13 07:58:22 EDT 2009

On Mar 13, 2009, at 7:52 AM, Morgan Aldridge wrote:

> On Fri, Mar 13, 2009 at 12:09 AM, Chai Lin <taycl at antlabs.com> wrote:
>> May I know what the maximum limit for maxqueued is? Can I monitor 350
>> machines by changing the mxqueued => 350 or more?
> Contrary to the documentation, in sysmon-0.93-pre3, maxqueued defaults
> to 75 not 100. There is a cieling_max_queued variable that is set
> based on the OSes maximum number of open files, so it depends on your
> system.

	I have to look at the source to remember.

> Judging by the documentation and a _very_ quick browse through
> syswatch.c, it sounds like maxqueued is just for how many checks can
> be in the queue at any given time. So, if the queue can be filled up
> and emptied multiple times in the queuetime then you might not need to
> change it. But, I could definitely wrong considering how quickly I
> looked at the code.
> Can you successfully monitor 350+ machines without changing maxqueued
> and without error? You might also try running sysmon in debug mode to
> look for 'walk_queue_checks_add' & 'walk_queue_checks' lines. In
> addition to increasing maxqueued, if needed, you might consider
> increating queuetime from the default of 60 seconds.
> I haven't personally run more than about 50-60 tests in one sysmon
> config, but I think Jared had designed it to handle a lot of tests.
> I hope that helps and is reasonably accurate.

	This sounds correct.  I've had hundreds/thousands of things that get  
queued at a time because their timer 'pops'.  This happens when  
monitoring a large network including all the infrastructure and cpe  

	I've neglected the code for awhile, are there significant outstanding  
defects that I need to address?  Features that should be added?

	- Jared

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