guide/ops/troubleshooting/increase-system-resource-limits.md - brooklyn-docs - Git at Google

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 layout: website-normal
 title: Increase System Resource Limits
 toc: /guide/toc.json
 ---

 If you encounter the following error:

     Caused by: java.io.IOException: Too many open files
             at java.io.UnixFileSystem.createFileExclusively(Native Method)[:1.8.0

 Please check and increase the limit for opened files.

 If you encounter the error below, e.g. when running with many entities, please consider **increasing the ulimit**:

     java.lang.OutOfMemoryError: unable to create new native thread

 On the VM running Apache Brooklyn, it is recommended that nproc and nofile are reasonably high
 (e.g. 16384 or higher; a value of 1024 is often the default).

 ## For Centos 7
 To check the current limits, you will need to know the PID for the brooklyn process. You can find
 this by running `systemctl status brooklyn` and checking the `Main PID` line.

 To see the current limits, run `cat /proc/<brooklyn PID>/limits` replacing <brooklyn PID> with the Main PID
 from above

 To override the default limits, you will need to create a `limits.conf` and populate it with the required
 values as follows:

 ```
 mkdir -p /etc/systemd/system/brooklyn.service.d

 cat > /etc/systemd/system/brooklyn.service.d/limits.conf << EOF
 [Service]
 LimitNOFILE=16384
 LimitNPROC=16384
 EOF
 ```

 You will then need to reload the systemctl daemon and restart brooklyn:

 ```
 systemctl daemon-reload
 systemctl restart brooklyn
 ```

 To check the new limits, you will need to obtain the new brooklyn PID by running `systemctl status brooklyn`
 and `cat`ing the process limits as above


 ## For Centos 6
 Please check the limit for opened files `cat /proc/sys/fs/file-max` and increase it.
 You can increase the maximum limit of opened files by setting `fs.file-max` in `/etc/sysctl.conf`.
 and then running `sudo sysctl -p` to apply the changes.

 If you want to check the current limits run `ulimit -a`. Alternatively, if Brooklyn is run as a
 different user (e.g. with user name "brooklyn"), then instead run `ulimit -a -u brooklyn`.

 For RHEL (and CentOS) distributions, you can increase the limits by running
 `sudo vi /etc/security/limits.conf` and adding (if it is "brooklyn" user running Apache Brooklyn):

     brooklyn           soft    nproc           16384
     brooklyn           hard    nproc           16384
     brooklyn           soft    nofile          16384
     brooklyn           hard    nofile          16384

 Generally you do not have to reboot to apply ulimit values. They are set per session.
 So after you have the correct values, quit the ssh session and log back in.

 For more details, see one of the many posts such as
 [http://tuxgen.blogspot.co.uk/2014/01/centosrhel-ulimit-and-maximum-number-of.html](http://tuxgen.blogspot.co.uk/2014/01/centosrhel-ulimit-and-maximum-number-of.html).
	---
	layout: website-normal
	title: Increase System Resource Limits
	toc: /guide/toc.json
	---

	If you encounter the following error:

	Caused by: java.io.IOException: Too many open files
	at java.io.UnixFileSystem.createFileExclusively(Native Method)[:1.8.0

	Please check and increase the limit for opened files.

	If you encounter the error below, e.g. when running with many entities, please consider increasing the ulimit:

	java.lang.OutOfMemoryError: unable to create new native thread

	On the VM running Apache Brooklyn, it is recommended that nproc and nofile are reasonably high
	(e.g. 16384 or higher; a value of 1024 is often the default).

	## For Centos 7
	To check the current limits, you will need to know the PID for the brooklyn process. You can find
	this by running `systemctl status brooklyn` and checking the `Main PID` line.

	To see the current limits, run `cat /proc/<brooklyn PID>/limits` replacing <brooklyn PID> with the Main PID
	from above

	To override the default limits, you will need to create a `limits.conf` and populate it with the required
	values as follows:

	```
	mkdir -p /etc/systemd/system/brooklyn.service.d

	cat > /etc/systemd/system/brooklyn.service.d/limits.conf << EOF
	[Service]
	LimitNOFILE=16384
	LimitNPROC=16384
	EOF
	```

	You will then need to reload the systemctl daemon and restart brooklyn:

	```
	systemctl daemon-reload
	systemctl restart brooklyn
	```

	To check the new limits, you will need to obtain the new brooklyn PID by running `systemctl status brooklyn`
	and `cat`ing the process limits as above


	## For Centos 6
	Please check the limit for opened files `cat /proc/sys/fs/file-max` and increase it.
	You can increase the maximum limit of opened files by setting `fs.file-max` in `/etc/sysctl.conf`.
	and then running `sudo sysctl -p` to apply the changes.

	If you want to check the current limits run `ulimit -a`. Alternatively, if Brooklyn is run as a
	different user (e.g. with user name "brooklyn"), then instead run `ulimit -a -u brooklyn`.

	For RHEL (and CentOS) distributions, you can increase the limits by running
	`sudo vi /etc/security/limits.conf` and adding (if it is "brooklyn" user running Apache Brooklyn):

	brooklyn soft nproc 16384
	brooklyn hard nproc 16384
	brooklyn soft nofile 16384
	brooklyn hard nofile 16384

	Generally you do not have to reboot to apply ulimit values. They are set per session.
	So after you have the correct values, quit the ssh session and log back in.

	For more details, see one of the many posts such as
	[http://tuxgen.blogspot.co.uk/2014/01/centosrhel-ulimit-and-maximum-number-of.html](http://tuxgen.blogspot.co.uk/2014/01/centosrhel-ulimit-and-maximum-number-of.html).