[collectd] Varnish plugin

[Jerome Renard]

Florian,

On Fri, Jun 11, 2010 at 10:51 AM, Florian Forster <octo at verplant.org> wrote:
> Hi Jérôme,
>
> On Fri, Jun 11, 2010 at 08:40:30AM +0200, Jerome Renard wrote:
>> Are you still running the plugin on your production machines ?
>> Did you nothing any (new ?) issue so far ?
>
> I've changed the data sets / types used for storing the values
> yesterday. Some of the values are "gauge" values while most of them are
> "counters". The plugin now uses generic data sets with gauge or derive
> data sources, as needed.

I tested your changes and I am afraid there is either something wrong
or I overlooked something.

I tested the "cache_result" type, and when the DERIVE type is used, I
do not get the correct numbers.
If I compare the output I get from varnishstat and the result I get
from the rrd generated graphs the values
are completely different. I guess this is due to de derive type. So
since the cache_hit, cache_mit and cache_hitpass
are simpler counters as explained in the documentation [1] I tried to
modify the types.db file and I added the varnish_submit_counter
function.

But the problem is that I never get any value, it is always set to
zero, here is what I get from the debug:

[...]

plugin_read_thread: Handling `varnish/localhost'.
plugin_dispatch_values: time = 1276276636; interval = 10; host =
debian-collectd; plugin = varnish; plugin_instance = ; type =
cache_result; type_instance = hit;
uc_update: debian-collectd/varnish/cache_result-hit: ds[0] = 0.000000
plugin: plugin_write: Writing values via rrdtool.

rrdtool plugin: rrd_cache_insert: file =
debian-collectd/varnish/cache_result-hit.rrd; values_num = 11; age =
100;
plugin_dispatch_values: time = 1276276636; interval = 10; host =
debian-collectd; plugin = varnish; plugin_instance = ; type =
cache_result; type_instance = miss;
uc_update: debian-collectd/varnish/cache_result-miss: ds[0] = 0.000000
plugin: plugin_write: Writing values via rrdtool.

[...]

The modifications I made look like this :
- http://gist.github.com/434781

Did I overlook something ?

Thanks in advance for your feedback

1. http://varnish-cache.org/wiki/StatsExplained

--
Jérôme :)