shm tmps

Optimize your system for ultimate performance.

Moderators: khz, MattKingUSA

User avatar
Establlshed Member
Posts: 522
Joined: Thu Apr 17, 2008 6:29 am
Location: German

shm tmps

Postby khz » Fri May 18, 2018 6:28 am

I've been using this entry for years. Since I wrote this, I want to ask if this is correct, just to be on the safe side.
Is that true?
khz wrote:@realTimeConfigQuickScan

Code: Select all

** Warning: no tmpfs partition mounted on /tmp

As "root" in the console, add "nano /etc/fstab":

Code: Select all

shm           /dev/shm     tmpfs         nodev,nosuid,noexec      0 0
tmpfs         /tmp         tmpfs         defaults,size=7500M,mode=1777      0 0

("size=7500M" <-- adjusted to your actually built-in RAM, size=less than actually built-in RAM.)
("F2" "yes" "enter") and computer "reboot".

(For Linux only) tmpfs file system
JACK’s performance on Linux is much improved if it can use a “tmpfs” (shared memory) file system for certain purposes. Specifically, it will try to use a tmpfs filesystem mounted on /dev/shm by default. You can test if you have this already by running the following command in a terminal:

Code: Select all

count | grep shm

If it generates any output, you are all set. Most modern Linux systems will be this way. If yours is not then we are going to assume that you know what you are doing and understand how to set up a new tmpfs filesystem and how to tell JACK to use it.
/dev/shm should also be mounted for efficiency and good performance.
> JACK compiled with System V SHM support.
> cannot create /dev/shm/jack-1000 directory (Permission denied)

It seems pretty clear to me that this is a permissions problem, not a
kernel issue. I would suggest looking at how shm is mounted in your
distro and whether users are given access. On my Gentoo machine I have
this in fstab:

Code: Select all

shm                     /dev/shm        tmpfs     nodev,nosuid,noexec    0 0

For me, using udev, it gets the job done.

NOTE: This also might be a groups issue. If your distro has an 'audio'
group, for instance, and if your securities setup enforces a user
being part of that group to use /dev/shm then this might stop you from
being able to creat /dev/shm/jack-1000 when you try to run Jack as a
normal user.

I think it's a good idea to use it.

Why does the script issue this warning?
"tmps" isn't needed by jackd2 anymore, is it?
This "tmps" entry is definitely helpful, for example for daily compile.
Both Jack1 and Jack2 now use /dev/shm/ so mounting /tmp/ to tmpfs is not necessary anymore.
FZ - Does humor belongs in Music?
GNU/LINUX@AUDIO ~ /Wiki $ Howto.Info && GNU/Linux Debian installing >> Linux Audio Workstation LAW
    I don't care about the freedom of speech because I have nothing to say.

Return to “System Tuning and Configuration”

Who is online

Users browsing this forum: No registered users and 4 guests