rcon

rcon is a lightweight resource virtualization tool for linux processes. rcon is one-binary.

demo

build

build on vagrant

vagrant up
vagrant ssh
cd rcon/
rake
cp -p mruby/bin/rcon /path/to/bin-dir/.

build packages and release

Create release binary considering glibc versions using Docker.

Require: golang docker

I build and release rcon on macOS.

rake package
ls -l pkg/
GITHUB_TOKEN=`cat ~/.github_token` rake release

usage

 ./rcon --help
Usage: rcon [options] --user username --command "yes >> /dev/null"
    --cpu VAL
      default: 30 (%)
    --memory VAL
      default: 512000000 (Byte)
    --read VAL
      default: 10485760 (Byte/sec)
    --write VAL
      default: 10485760 (Byte/sec)
    --group VAL
      default: rcon
    --dev VAL
      default: 8:0
    --pids VAL
      default: nothing
    --version

cpu example

no limit

• command

yes >> /dev/null

• cpu usage

  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
27577 matsumot  20   0 98.5m  608  520 R 100.0  0.0   0:01.95 yes 

limitting cpu 10%

• command

sudo ./rcon --user matsumotory --command "yes >> /dev/null" --cpu 10

• cpu usage limitted 10% by rcon

  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
23941 matsumot  20   0 98.5m  604  520 R  9.6  0.0   0:00.63 yes

limitting already running process to cpu 30%

• command

yes >> /dev/null &
yes >> /dev/null &
sudo ./rcon --pids "`pgrep yes`"

• cpu usage

  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND 
22531 vagrant   20   0 98.5m  612  524 R 15.6  0.0   0:16.16 yes
22532 vagrant   20   0 98.5m  612  524 R 14.3  0.0   0:15.47 yes

Notice: pids optsion don't delete groups after running process was finished

io example

no limit

• command

dd if=/dev/zero of=tempfile bs=1M count=1000 oflag=direct

• io usage

  TID  PRIO  USER     DISK READ  DISK WRITE  SWAPIN     IO>    COMMAND
27569 be/4 matsumot    0.00 B/s   22.09 M/s  0.00 % 95.93 % dd if=/dev/zero of=tempfile bs=1M count=1000 oflag=direct

limitting write io 1MByte/sec

• command

sudo ./rcon --user matsumotory --command "dd if=/dev/zero of=tempfile bs=1M count=1000 oflag=direct" --write 1024000

• io usage limitted 1MByte/sec by rcon

  TID  PRIO  USER     DISK READ  DISK WRITE  SWAPIN     IO>    COMMAND
24676 be/4 matsumot    0.00 B/s  995.77 K/s  0.00 % 99.99 % dd if=/dev/zero of=tempfile bs=1M count=1000 oflag=direct  

• find io dev id (--dev)

$ ls -l /dev/xvda | awk '{print $5 $6}' | sed 's/,/:/'
202:0

for --dev option. default 8:0.