Raising minimum & recommended disk requirements for Centmin Mod LEMP installs

After a lot of testing on various VPSes and various VPS providers' provided CentOS OS image templates over time, the disk usage patterns are becoming clearer. Some VPS providers have heavy default CentOS OS images than others and Centmin Mod LEMP's automated backup routines for Nginx configuration, ccache compiler cache and source download compilations require more disk space as time goes by. So today, I revised the Centmin Mod LEMP stack's minimum & recommended disk space requirements to better meet these patterns of usage.

From Centmin Mod LEMP Stack Install Nginx on CentOS the revised disk usage requirements are:

A quick list of routines where disk space usage grow over time.

Nginx Auto Backup Routine

Everytime you run centmin.sh menu option 4 to upgrade, downgrade or recompile Nginx server, a backup of the Nginx configuration files and ssl certificates are made to timestamped directories within /usr/local/nginxbackup

Code:

du -h --max-depth=1 /usr/local/nginxbackup/
588K    /usr/local/nginxbackup/confbackup
11M     /usr/local/nginxbackup/nginxdirbackup
11M     /usr/local/nginxbackup/

ccache Source Compiler Cache

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Centmin Mod source compiles Nginx and PHP-FPM and a select few PHP extensions. And to speed up recompiles, Centmin Mod installs and uses ccache source compiler caching. The ccache allows recompiles to be up to 60+% faster. The ccache cache storage is at /home/.ccache.

To see current ccache storage stats and disk usage

Code:

du -sh /home/.ccache/
ccache -s

Code:

du -sh /home/.ccache/
292M    /home/.ccache/

Code:

ccache -s
cache directory                     /home/.ccache
primary config                      /home/.ccache/ccache.conf
secondary config      (readonly)    /usr/local/etc/ccache.conf
cache hit (direct)                  2679
cache hit (preprocessed)            4007
cache miss                          6318
called for link                      345
called for preprocessing             612
compile failed                       215
preprocessor error                   104
bad compiler arguments               115
unsupported source language          114
autoconf compile/link               1926
no input file                        243
files in cache                     18222
cache size                         317.3 MB
max cache size                       2.2 GB

To clear ccache disk space use command

Code:

ccache -C

Source download directory /svr-setup

All Centmin Mod source and other required downloaded files are saved at /svr-setup and over time this can grow. You could nuke everything in this directory and Centmin Mod will redownload what's needed but overtime this will grow. The next Centmin Mod 123.09beta01 and higher have smarter routines to only keep the last and most recent version of largest downloads like php, nginx_pagespeed, nginx, openssl, libressl etc.

Code:

du -sh /svr-setup
1.8G    /svr-setup/

10 largest directories in /svr-setup

Code:

du --max-depth=1 /svr-setup/ | sort -k1 -n | tail -10
20824   /svr-setup/mongodb-1.1.1
25068   /svr-setup/libevent-release-2.0.22-stable
29524   /svr-setup/openssl-1.0.2f
54412   /svr-setup/nginx-1.9.10
111496  /svr-setup/libressl-2.2.6
236052  /svr-setup/php-5.6.16
252748  /svr-setup/php-7.0.1
253036  /svr-setup/php-7.0.2
609388  /svr-setup/ngx_pagespeed-release-1.9.32.13-beta
1883568 /svr-setup/

dbbackup.sh MySQL Backup Script

For Premium members who have access to dbbackup.sh MySQL backup script, they'll have a growing number of MySQL backup files occupying local disk space.

Swap and /tmp

Also auto creation of a larger on disk /tmp filesystem if you're on a very low memory system as ramdisk based /tmp would not be sufficient if you have low memory amount installed and utilise MySQL which uses /tmp. Centmin Mod 123.09beta01+ and higher also add an on disk based swap file if one is not detected and the size of the swap file created is dynamically determined based your available disk free space and amount of memory installed on your system.

An example on a 1GB memory 20GB disk with 19GB free space which initially didn't have a swap file, would after Centmin Mod install have a ~950MB /tmp file created on disk and a 1023MB swap file on disk.