Hhvm: Unable to open pid file /run/hhvm.pid for write

[ahmadazimi]

HHVM Version

3.17.1 on Centos 7

Standalone code, or other way to reproduce the problem

hhvm -m daemon -u nginx -c /etc/hhvm/server.ini

Expected result

Actual result

_Unable to open pid file /run/hhvm.pid for write_

I know this is not a fatal error, but when I run the hhvm daemon, the following error saved in error.log:
Unable to open pid file /run/hhvm.pid for write

My server.ini looks like this

[jazzdan]

Does the nginx user have permissions to write to the /run directory?

[mofarrell]

HHVM typically puts the pid file in /var/run/hhvm/hhvm.pid The/run (or /var/run they are symlinked) directory is actually a mounted tmpfs filesystem (on most linux distros), and will not survive a reboot. This means it is typically the job of an init.d script to setup the appropriate skeleton directories and permissions. In the case of our distributed packages, this happens here: https://github.com/hhvm/packaging/blob/master/hhvm/deb/skeleton/etc/init.d/hhvm#L57

[ahmadazimi]

@jazzdan No! nginx user doesn't have permissions to write to the /run directory.

I use below service file to start and stop hhvm daemon. So, is that above mentioned error important? And should I fix it?

[Unit]
Description=HipHop Virtual Machine

[Service]
PIDFile=/run/hhvm.pid
ExecStart=/usr/local/bin/hhvm -m daemon -u nginx -c /etc/hhvm/server.ini
ExecReload=/bin/kill -s HUP $MAINPID
KillSignal=SIGQUIT
TimeoutStopSec=5
KillMode=process
PrivateTmp=true

[Install]
WantedBy=multi-user.target

[jazzdan]

@ahmadazimi you should fix it. I would create the /var/run/hhvm directory and give the nginx user permissions to write to that directory. You could do this as a component of your service file, or as part of your configuration management system that installs HHVM.

[mofarrell]

In your systemd unit add:

RuntimeDirectory=hhvm
User=nginx

Remove the -u nginx from the ExecStart string.
Switch the pid file to be /var/run/hhvm/hhvm.pid for both the unit, and the hhvm config.

I haven't tested this, but it should work for getting the PID file setup with proper permissions.
This is not an issue with HHVM, so I am closing this issue.

[ahmadazimi]

@mofarrell & @jazzdan Thanks for great help.
Now hhvm starts without any errors.

My final hhvm.service (to help others, if they come here):

[Unit]
Description=HipHop Virtual Machine

[Service]
PIDFile=/run/hhvm/hhvm.pid
ExecStart=/usr/local/bin/hhvm -m daemon -c /etc/hhvm/server.ini
ExecReload=/bin/kill -s HUP $MAINPID
KillSignal=SIGQUIT
TimeoutStopSec=5
KillMode=process
PrivateTmp=true
RuntimeDirectory=hhvm
User=nginx

[Install]
WantedBy=multi-user.target