proc_open() fork failed – Cannot allocate memory

The proc_open(): fork failed - Cannot allocate memory error can occur when using the proc_open() function in PHP. This error can be solved by memory size.

The "proc_open(): fork failed - Cannot allocate memory" error occurs when a process cannot be created due to lack of memory. This error often occurs in PHP scripts that use the proc_open() function to execute external programs.

To solve this error, you can try the following solutions:

  1. Increase memory limit: You can increase the memory limit in your PHP configuration file. For example, you can add the following line to your php.ini file:

     memory_limit = 256M
  2. This will increase the memory limit to 256 megabytes.

  3. Free up memory: You can try freeing up memory on your server by stopping other processes that are using too much memory.

  4. Optimize code: You can optimize your code to use less memory by avoiding unnecessary variable allocations and freeing up memory when it is no longer needed.

  5. Increase swap space: You can increase the swap space on your server to provide additional virtual memory.

    To activate swap space:

     sudo swapon /dev/sda1    

    To deactivate swap space:

     sudo swapoff /dev/sda1   


     /bin/dd if=/dev/zero of=/var/swap.1 bs=1M count=1024
    /sbin/mkswap /var/swap.1
    /sbin/swapon /var/swap.1   

To check the status of swap space and the amount of memory being used, you can use the free command with the -h option to display the output in a human-readable format:

 free -h

This will display the total, used, and free memory on your system, including the swap space.

Note that you typically need root privileges to use the swapon and swapoff commands.