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I have Postgre installed.
If i type find/dev -type f -exec ls -l {} \;

-rw -------. 1**50128 Nov 28 13:38 /dev/shm/PostgreSQL.****

is output.

When I looked at various things about/dev/shm /, it was written as follows, and it was read that the program or process was temporarily used as shared memory.

/dev/shm is used as a mount point for the RAM disk. In/etc/fstab,/dev/shm operates as a memory file system because tmpfs is specified as the file system. Writing a file to/dev/shm does not actually write to the disk, so it will disappear after the OS reboot.

/dev/shm is nothing but implementation of traditional shared memory concept.It is an efficient means of passing data between programs.One program will create a memory portion, which other processes (if permitted) can access.This will result into speeding up things on Linux.

shm/shmfs is also known as tmpfs, which is a common name for a temporary file storage facility on many Unix-like operating systems.It is intended to appear as a mounted file system, but one which uses virtual memory instead of a persistent storage device.

Therefore, when PostgreSQL is installed, it will be created in the following directory. . I think,
I didn't know the purpose of use or details even after examining it.

/dev/shm/PostgreSQL ***

Someone in the above directory/dev/shm/PostgreSQL ***
Do you know more about? Thank you.

  • Answer # 1

    I don't know the specific reason for PostgreSQL,
    In general, you may be using/dev/shm/to share information across multiple processes.
    Parallel processing or something that works in concert.

    It seems to be related to

    settingdynamic_shared_memory_type = posix.
    Files are created under/dev/shm/at runtime, not during PostgreSQL installation.