Home / server / Questions / 842046
In Process
sastorsl
Asked: 2017-04-03 02:38:15 +0800 CST

systemd: Limit concurrent start at boot for a custom service

  • 772

We have defined a "[email protected]" file which handles our application server starts. On some servers there are a lot of application servers and we hit issues where one or two servers won't start.

This is a RedHat Enterprise Linux 7 server.

Is there a way to limit the number of concurrent / simultaneous processes for this one service?

The service file:

[Unit]
Description=Appserver Instance %i
After=network.target

[Service]
Type=forking
ExecStart=/custom/server start %i
ExecStop=/custom/server stop %i
PIDFile=/custom/servers/.pid/%i.pid
User=%i
SuccessExitStatus=1
TimeoutStartSec=600
TimeoutStopSec=60

[Install]
WantedBy=multi-user.target

Target is that all servers should start, but at boot time I don't want all of them to start at the same time. They should all be able to run at the same time.

linux

1 Answers

  1. If you don't care about the ordering, you can use an ExecStartPre with a small variable sleep. ExecStartPre=/bin/bash -c 'sleep $(( RANDOM % 5 ))' should make batch them into five buckets, each delayed by a second. If you need to control the order, you can use a .path unit per instance and a limiter that touches the paths in the order you want.

    • 0