Watcher + munin

Watcher + munin

[Troex Nevelin]

I run Raindrops::Watcher and have put "Active Mean" and "Queued Mean"
on the graph here:
http://mon.melkov.net/PeterHost-RU/spb1.melkov.net/raindrops_watcher.html

Munin reads X-Mean for active and queued connections on the socket
each 5 minutes and after send's reset POST.


Do I understand correctly that "Queued X-Mean" is average queue lenght?
"Active X-Mean" looks like the avaerage number of workers used over the
time after reset.

Why I ask is because I cannot understand what "last_data_recv" means?

X-Mean - mean last_data_recv time recorded (rounded, in milliseconds)
^^^ why this value is in milliseconds? Do you mean CPU seconds?

Re: Watcher + munin

[Eric Wong]

Troex Nevelin <list@mrtech.ru> wrote:
> Do I understand correctly that "Queued X-Mean" is average queue lenght?
> "Active X-Mean" looks like the avaerage number of workers used over the
> time after reset.

Yes, your understanding is correct.  My documentation is bogus, patch
below (pushed out to raindrops.git and the website)

> Why I ask is because I cannot understand what "last_data_recv" means?
> 
> X-Mean - mean last_data_recv time recorded (rounded, in milliseconds)
> ^^^ why this value is in milliseconds? Do you mean CPU seconds?

>From cb90a12dec7b1c55ebae5a83bafa15f415b576da Mon Sep 17 00:00:00 2001
From: Eric Wong <normalperson@yhbt.net>
Date: Thu, 24 Mar 2011 13:35:32 -0700
Subject: [PATCH] watcher: fix documentation for X-* headers

I copied and pasted off the Raindrops::LastDataRecv
documentation.  While the headers and mathematical meanings are
identical, they measure different things (but for the same
purpose)

Noticed-by: Troex Nevelin
---
 lib/raindrops/watcher.rb |   16 ++++++++--------
 1 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/lib/raindrops/watcher.rb b/lib/raindrops/watcher.rb
index ada921a..6ecd3ed 100644
--- a/lib/raindrops/watcher.rb
+++ b/lib/raindrops/watcher.rb
@@ -72,19 +72,19 @@ require "aggregate"
 # - active_min - do not stream a line until this active count is reached
 # - queued_min - do not stream a line until this queued count is reached
 #
-# == Response headers (mostly the same as Raindrops::LastDataRecv)
+# == Response headers (mostly the same names as Raindrops::LastDataRecv)
 #
-# - X-Count   - number of requests received
+# - X-Count   - number of samples polled
 # - X-Last-Reset - date since the last reset
 #
 # The following headers are only present if X-Count is greater than one.
 #
-# - X-Min     - lowest last_data_recv time recorded (in milliseconds)
-# - X-Max     - highest last_data_recv time recorded (in milliseconds)
-# - X-Mean    - mean last_data_recv time recorded (rounded, in milliseconds)
-# - X-Std-Dev - standard deviation of last_data_recv times
-# - X-Outliers-Low - number of low outliers (hopefully many!)
-# - X-Outliers-High - number of high outliers (hopefully zero!)
+# - X-Min     - lowest number of connections recorded
+# - X-Max     - highest number of connections recorded
+# - X-Mean    - mean number of connections recorded
+# - X-Std-Dev - standard deviation of connection count
+# - X-Outliers-Low - number of low outliers (hopefully many for queued)
+# - X-Outliers-High - number of high outliers (hopefully zero for queued)
 #
 # = Demo Server
 #
-- 
Eric Wong