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Server Status Logger / hpptd to run via crontab
Apache httpd - log files and log tools example from a Well House Consultants training course
More on Apache httpd - log files and log tools [link]

This example is described in the following article(s):
   • Logging the performance of the Apache httpd web server - [link]
   • Tuning Apache httpd and Tomcat to work well together - [link]
   • Apache httpd Server Status - monitoring your server - [link]
   • Server logs - drawing a graph of gathered data - [link]

This example references the following resources:

Source code: statlog Module: A606
#!/usr/bin/env perl

=head1 Server Status Logger

This is a sample server status logger, based on the original idea by
Mark J Cox and shipped with Apache http server. It collects the server
status from mod_status and logs it to file; it also collect various
stats from the local machine (that's an addition). When run on the
web server, this gives a snapshot of how busy the server is and of
memory use. Logged under crontab, this allows a picture to be built
up at regular intervals.

Sample Crontab line:

1-59/4 * * * * /home/wellho/serverstatus/statlog

Note that mod_status needs to be set up and configured to allow responses
to be sent to the host you're running on, that file / directory permissions
need to be set, etc, to run this code.

Sample output line (folded here for clarity):

062901 3486 14054 1.61201 2348 1.48467 6129.17 4128.31 4 6
_._K_K_W.W_..._ 0.62 0.33 0.27 904528 878548 25980 0 9328
606704 262516 642012 2048276 33324 2014952

Graham Ellis / Well House Consultant / 2010. See


use LWP;

@timeels = localtime();
$logfile = sprintf("/home/wellho/serverstatus/%4d%02d%02d_statlog.txt",
@fields = (sprintf("%02d%02d%02d",@timeels[2,1,0]));

$ua = LWP::UserAgent->new(agent => "System Monitor");
$resp = $ua->get("");

if (($status = $resp->code()) != 200) {
        die ("$0 response code $status\n");

foreach $line (split(/\n/,$resp->decoded_content)) {
        ($key,$val) = $line =~ /([^:+]):\s*(\S+)/;
        $val =~ s/\.+$//;
        push @fields,$val;

# load average: 0.45, 0.33, 0.33
$up = `uptime`;
@xf = $up =~ /average:\s+(\S+),\s+(\S+),\s+(\S+)/;
push @fields,@xf;

# total used free shared buffers cached
# Mem: 904528 881252 23276 0 8020 630500
# -/+ buffers/cache: 242732 661796
# Swap: 2048276 33324 2014952

$free = `free`;
@fv = $free =~ /\s(\d+)\s/g;
push @fields,@fv;

open (FH,">>$logfile") or die ("$0 unable to open log file - $@\n");
$logline = join(" ",@fields);
print FH "$logline\n";
close FH;


Sample output line:

233301 51546 223194 .0201641 26086 1.976 8761.43 4433.92 7 7
WK.C___.._K_K_WK....._ 0.15 0.18 0.24 904528 823380 81148 0 10764
561376 251240 653288 2048276 43244 2005032

Which means:

0 Timed at: 23:33:01
1 Total Accesses: 51546
2 Total kBytes: 223194
3 CPULoad: .0201641 (i.e. 2%)
4 Uptime: 26086 (seconds httpd has been running)
5 ReqPerSec: 1.976
6 BytesPerSec: 8761.43
7 BytesPerReq: 4433.97
8 BusyWorkers: 7
9 IdleWorkers: 7
10 Scoreboard: WK.C___.._K_K_WK....._
11 System load average last 1 minute: 0.15
12 System load average last 5 minutes: 0.18
13 System load average last 15 minutes: 0.24
14 Memory, total: 904528 (kb, excludes kernel)
15 Memory, used: 823380 (all figs in kb ...)
16 Memory, free: 81148
17 Memory, shared: 0
18 Memory, buffers: 10764
19 Memory, cached: 561376
20 buffers/cache used: 251240
21 buffers/cache free: 653228
22 Swap space free: 2048276
23 Swap space used: 43244
24 Swap space total: 2005032

Scoreboard key:
"_" Waiting for Connection, "S" Starting up, "R" Reading Request,
"W" Sending Reply, "K" Keepalive (read), "D" DNS Lookup,
"C" Closing connection, "L" Logging, "G" Gracefully finishing,
"I" Idle cleanup of worker, "." Open slot with no current process

This log truncates trailing "."s off the scoreboard, so any slots
not listed will be open with no current process.

Learn about this subject
This module and example are covered on the following public courses:
 * Deploying Apache and Tomcat
 * Deploying Java Applications on Linux / Unix
Also available on on site courses for larger groups

Books covering this topic
Yes. We have over 700 books in our library. Books covering Lamp deployment are listed here and when you've selected a relevant book we'll link you on to Amazon to order.

Other Examples
This example comes from our "Apache httpd - log files and log tools" training module. You'll find a description of the topic and some other closely related examples on the "Apache httpd - log files and log tools" module index page.

Full description of the source code
You can learn more about this example on the training courses listed on this page, on which you'll be given a full set of training notes.

Many other training modules are available for download (for limited use) from our download centre under an Open Training Notes License.

Other resources
• Our Solutions centre provides a number of longer technical articles.
• Our Opentalk forum archive provides a question and answer centre.
The Horse's mouth provides a daily tip or thought.
• Further resources are available via the resources centre.
• All of these resources can be searched through through our search engine
• And there's a global index here.

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