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Joomla and mysterious memory usage

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I've been running a server which has a fairly busy Joomla site on it. The server has 2Gb RAM, and is running nginx, php5-fpm and mysql, and not much else. However it would run for a while and then the disk would start swapping out. Not a lot, but enough to cause a few issues. If I restarted the server, memory usage would start at something like this

>$ free
 total       used       free
 Mem:       2048036    1024048     1023988
 Swap:      4192960          0    4192960

After about a day it would look like this

>$ free
             total       used       free    
Mem:       2048036    1924048      73988   
Swap:      4192960          0    4192960

And eventually it would have a flurry of activity which would make it look like this

>$ free
             total       used       free    
Mem:       2048036    1924048      23988   
Swap:      4192960       4567     4188393

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Summarizing dig Info with a bash script.

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Dig is a great tool, but most of its output is not very interesting. There are a bunch of command line options that I can never remember without a quick 'man dig' which always sounds a bit odd. So I whipped up a quick script. It takes a domain name as the argument, and then pumps out the Reverse IP lookup, Nameservers, and Mail servers with reverse lookup of their IPs.

#!/bin/bash
QUERYDOMAIN=$1
echo "Reverse IP:"
 echo "    " `dig x +short $QUERYDOMAIN`
 echo "Nameservers"
 NAMESERVERS=`dig ns +short $QUERYDOMAIN | sed "s/^[0-9]* //g"`
 for SERVER in $NAMESERVERS;
 do
 echo "    " $SERVER " = " `dig x +short $SERVER`;
 done
 echo "Mail Servers:"
 MAILSERVERS=`dig mx +short $QUERYDOMAIN | sed "s/^[0-9]* //g"`
 for SERVER in $MAILSERVERS;
 do
 echo "    " $SERVER " = " `dig x +short $SERVER`;
 done

The output looks like this:

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Munin, nginx, mysql on Ubuntu 11.04: Great tool. Poorly explained.

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Well I just jumped through the hoops again installing a new tool, and as it took me quite a while, I thought I'd help the Internet at Large through it. Or at least make a few notes, as most of my own searches for information on this drew blanks. I even went to the lengths of translating a few obscure German posts in case they could help.

Anyway, munin, once you get it going, is actually quite cool. It provides you with a graphical look at your server performance, and you can customise which data you collect quite simply. I'm installing it on an Ubuntu server 11.04, with nginx and mysql. I'm expecting a big traffic spike in the near future, so I want to see how the machine is handling it, and which bits, if any, are struggling.

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Ubuntu 11.10, Unity, Gnome 3 and the whole mess

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My main work machine is still on Ubuntu 10.10. I had installed 11.04 on my spare laptop, but hated Unity so much I only ever booted into Gnome Classic. I was hoping things might get better with 11.10, but things are now very much worse. To the point where I'm looking around for other distributions. I suspect, like Linus Torvalds, I might start looking at XFCE.

Anyway, after upgrading my laptop to 11.10, I was disturbed to find it wouldn't boot up: you just sit there looking at a message which says "Waiting for network configuration". I'm fairly techy (and have a spare computer), so I was able to find the answer, which was to drop to a shell and move a bunch of files from /var/run to /run. But imagine a non-techy person trying to cope with this. Congratulations Ubuntu, you just lost market share.

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