Jstats is a tiny resource monitor for jails, small tool that I wrote for FreeBSD systems - lists RAM, CPU and disk space usage of the jails running in the host system.
Tested On: FreeBSD 13.1 with standard jails defined within /etc/jail.conf file.
I like raw, homemade jails, digging around in config files. I don't use any jail management tool/package, being a minimal&analogue guy with a try-to-do-it-yourself spirit, I never tested jstats with jails created by jail management packages, such as; BastilleBSD, iocage, cbsd, et cetera.
But while it's all in the kernel, it shouldn't matter which jail manager you use; jstats should work.
Usage and a sample run:
[root@ozgur:~]# chmod +x jstats.sh
[root@ozgur:~]# ./jstats.sh
#Alternatively you might wish to move it somewhere inside $PATH for easier access;
[root@ozgur:~]# chmod +x jstats.sh
[root@ozgur:~]# mv jstats.sh /usr/local/bin/jstats
[root@ozgur:~]# jstats
==============================
jstats 0.1 by Ozgur Kazancci
https://ozgurkazancci.com
==============================
------------
Jails Found:
------------
nginxsrv 10.10.10.2
phpserver 10.10.10.3
sqlserver 10.10.10.4
------------------
Jails - RAM usage:
[kB] - [MB] - [GB]
------------------
nginxsrv: 2.1%
42908 kB - 42.908 MB - 0.042908 GB
phpserver: 2.2%
45540 kB - 45.54 MB - 0.04554 GB
sqlserver: 5.6%
112416 kB - 112.416 MB - 0.112416 GB
Total RAM usage: 9.9%
------------------
Jails - CPU usage:
------------------
nginxsrv: 2.1%
phpserver: 3.3%
sqlserver: 7.5%
Total CPU usage: 12.9%
-------------------------
Jails - Disk space usage:
-------------------------
1.3G /jails/nginxsrv
1.7G /jails/phpserver
1.4G /jails/sqlserver
[root@ozgur:~]# 
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