NodeJS error “EMFILE, too many open files” on Mac OS

Question

For sometime I am having the following error:

Error: EMFILE, too many open files  \'/Users/blagus/Gallery/Websites/Nicsware/Pills/resources/core/auth.node.js         


        

Answer 1

This worked for me:

ulimit -n 10480

found here

Answer 2

Check your ulimit. For example initialy my ulimit on OSX was 256.

• Run ulimit -n to see the limit.
• Afterwards You can ulimit -n 1024 to set a higher limit.

Answer 3

You can solve this problem by increasing the maxfiles limit:

launchctl limit maxfiles 16384 16384 && ulimit -n 16384

Answer 4

I am using watchman. Which fixed this errors for me. Worth trying!!!

brew update
brew install watchman

Answer 5

ulimit is great if you are using the terminal but it only works if you are running your app from the same terminal tab ( or shell instance ). Launchctl is great but is systemwide. If you leave Launchctl limit maxfile alone, the soft limit is 256 and the hard limit is unlimited.

In a production environment, you will probably need to launch at startup and reboot on crash, which means the best answer for Mac OSX is to use a .plist file for each of your applications. I launch my node application using said plist file ( which runs at start up and reboots after crashing )... inside this file you can set the amount of files per application using the SoftResourcesLimit key.

<key>KeepAlive</key>
<true/>

<key>RunAtLoad</key>
<true/>

<key>SoftResourceLimits</key>
<dict>
<key>NumberOfFiles</key>
  <integer>16384</integer>
</dict>

Answer 6

Maximum files was reseted to 256 in OS X 10.10.3 Yosemite. This can lead to problems with npm installations. You can check this limit from terminal with command ulimit -n. In order to change this beyond 256, you need to create two configuration files.

The first property list file /Library/LaunchDaemons/limit.maxfiles.plist :

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
 <plist version="1.0">
    <dict>
      <key>Label</key>
        <string>limit.maxfiles</string>
      <key>ProgramArguments</key>
        <array>
          <string>launchctl</string>
          <string>limit</string>
          <string>maxfiles</string>
          <string>65536</string>
          <string>65536</string>
        </array>
      <key>RunAtLoad</key>
        <true/>
      <key>ServiceIPC</key>
        <false/>
    </dict>
  </plist>

The second property list file /Library/LaunchDaemons/limit.maxproc.plist :

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple/DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
  <plist version="1.0">
    <dict>
      <key>Label</key>
        <string>limit.maxproc</string>
      <key>ProgramArguments</key>
        <array>
          <string>launchctl</string>
          <string>limit</string>
          <string>maxproc</string>
          <string>2048</string>
          <string>2048</string>
        </array>
      <key>RunAtLoad</key>
        <true />
      <key>ServiceIPC</key>
        <false />
    </dict>
  </plist>

Set the proper ownership and rights:

sudo chown root:wheel /Library/LaunchDaemons/limit.maxfiles.plist
sudo chown root:wheel /Library/LaunchDaemons/limit.maxproc.plist
sudo chmod 644 /Library/LaunchDaemons/limit.maxfiles.plist
sudo chmod 644 /Library/LaunchDaemons/limit.maxproc.plist

Set the desired limits to bash profile file (.bashrc or .bashprofile or similar):

ulimit -n 65536
ulimit -u 2048

Make sure that the rights are the same for bash profile:

chmod 644 .your_bash_profile_file

Restart computer and check with ulimit -n max files. It should be 65536 and you should be able to change it anything below that.

Source: http://docs.basho.com/riak/latest/ops/tuning/open-files-limit/#Mac-OS-X