Question
How to increase vm.max_map_count in a Plesk for Linux server?
Answer
Note: if direct SSH access to the server is not possible, contact the server administrator for further assistance.
Note: if container virtualization is used, these steps should be applied on a hardware node side.
1.Connect to the server via SSH;
2.increase the default value of vm.max_map_count parameter. An example of how to do that is shown below:
#sysctl -w vm.max_map_count=655300
vm.max_map_count = 655300
Or:
#echo 655350 > /proc/sys/vm/max_map_count
3.To change it permanently edit /etc/sysctl.conf with a text editor and add the following parameter with the new value. For example:
vm.max_map_count=655350
4.Run the command to immediately apply the changes made in /etc/sysctl.conf:
#sysctl -p
Additional information
The file /etc/sysctl.conf contains the maximum number of memory map areas a process may have. Memory map areas are used as a side-effect of calling malloc, directly by mmap and mprotect, and also when loading shared libraries.
While most applications need less than a thousand maps, certain programs, particularly malloc debuggers, may consume lots of them, e.g. up to one or two maps per allocation.
The default value is 65536.