/dev/shm

dolphin77 · 12-29-2009, 03:26 PM

Greetings.

I am just curious. Can anyone explain to me in few words, what is /dev/shm. Why it is by default in /etc/fstab of slackware-13, slackware-current. What advantages/disadvanteges it gives for laptop and\or for desktop.

Thank you in advance,
Vladimir

cg40oz · 12-29-2009, 03:29 PM

Read this:
http://en.wikipedia.org/wiki/Shared_memory

dolphin77 · 12-29-2009, 04:22 PM

Thank you for your post, but

Quote:

Recent 2.6 Linux kernel builds have started to offer /dev/shm as shared memory in the form of a ramdisk, more specifically as a world-writable directory that is stored in memory with a defined limit in /etc/default/tmpfs. /dev/shm support is completely optional within the kernel config file. It is included by default in both Fedora and Ubuntu distributions, where it is most extensively used by the Pulseaudio application.

we do not have pulseaudio on Slackware. Why would we need /dev/shm. As far as I understood, it 'consumes' some part of RAM. And I do not see practical need for it on a simple desktop solution. Please correct me if I am wrong. I am not the programmer who would enjoy fast sharing data in between different hardware. I simply want to understand practical benefits of having this in fstab.

stormtracknole · 12-29-2009, 04:29 PM

Quote:

Originally Posted by dolphin77

Thank you for your post, but

we do not have pulseaudio on Slackware. Why would we need /dev/shm. As far as I understood, it 'consumes' some part of RAM. And I do not see practical need for it on a simple desktop solution. Please correct me if I am wrong. I am not the programmer who would enjoy fast sharing data in between different hardware. I simply want to understand practical benefits of having this in fstab.

I believe that if you are using the ati proprietary driver, then you need to have /dev/shm in your fstab.

dolphin77 · 12-29-2009, 04:33 PM

Quote:

Originally Posted by stormtracknole

I believe that if you are using the ati proprietary driver, then you need to have /dev/shm in your fstab.

Thank you too. I am on the open source stuff since September

stormtracknole · 12-29-2009, 04:39 PM

Oh, if you are also a user of qemu, then you will also need /dev/shm. Those are the only two that I know of.

piratesmack · 12-29-2009, 05:53 PM

When I run SlackBuilds, I set TMP to /dev/shm

Less writes to the harddisk.