Re: how to increase space for tmpfs /tmp

[Paul E Condon <pecondon@mesanetworks.net>]

On 20120331_061146, Tom H wrote:
> On Fri, Mar 30, 2012 at 4:44 PM, Paul E Condon
> <pecondon@mesanetworks.net> wrote:
> > On 20120329_095413, Andrei POPESCU wrote:
> >> On Mi, 28 mar 12, 16:58:03, Paul E Condon wrote:
> 
> 
> >> > > You could have also considered uncompressing the tarball somewhere else,
> >> > > like $HOME/tmp or $HOME/src, but it sure is a valid solution, especially
> >> >        ^^^^^^^^^    ^^^^^^^^^
> >> > On my computer that is running wheezy neither of these suggestions work,
> >> > because, I think, these are not mount points supporting access to external
> >> > physical disk hardware.
> >>
> >> You must be misunderstanding me, I meant "some directory in your home",
> >> because on most systems /home has enough space.
> >
> > No. You misunderstand me. There is a new extra requirement on TMPDIR, a
> > restriction on ones choise of its value. A directory entry on a disk
> > file system is not enough. It must be a directory entry that has a line
> > in /etc/fstab that enables its use as a mount point to real separate
> > partition. At least that is the way it is now. If this restriction were
> > removed by some change in the implementation that I know not how to do...
> > then your suggestion would likely work and the old way of using /tmp
> > would also work.
> 
> There's no extra requirement!
> 
> If you set up "/tmp" as a "real separate partition", that's the "/tmp"
> that the system'll use (it looks like it'll be a bind-mount over a
> tmpfs "/tmp" if you don't set "RAMTMP=no" in "/etc/default/rcS").
> 
> Pre-tmp-as-tmpfs, if you don't set up "/tmp" as a "real separate
> partition", "/tmp" is a directory on "/".
> 
> Post-tmp-as-tmpfs, if you don't set up "/tmp" as a "real separate
> partition", "/tmp" is a mount-point for a tmpfs filesystem the default
> "RAMTMP=yes" set in "/etc/default/rcS".
> 
> By default, the size of this filesystem is 20% of RAM because there
> are other tmpfs filesystems set up by default ("/run", "/run/lock",
> "/run/shm") and they've been sized, respectively, at 10% of RAM, 5MiB,
> 20% of RAM so that the total of tmpfs filesystems adds up to
> "50%+5MiB" for systems that don't have any swap set up to be able to
> operate in the event that the tmpfs filesystems are used up fully.
> 
> If you want a larger tmpfs "/tmp", you can change "TMP_SIZE" in
> "/etc/default/tmpfs" (or, untested, edit "/etc/fstab" and add a "tmpfs
> /tmp tmpfs size=xxx 0 0"). I'd mentioned earlier someone else's
> suggestion that you can set the maximum size of to RAM+SWAP. It's
> probably safer to set it to 20%_of_RAM+SWAP.
> 
> If you don't want to use tmpfs for "/tmp", you simply set "RAMTMP=no"
> in "/etc/default/rcS".
> 
> 
> > I never had a dedicated partion for /tmp and now it is required. That,
> > to me, is a change. I fixed it when I learned that it is now required,
> > and I think it would be nice to go back to the old way because the old
> > way did not require a separate partition. But I repeat myself. Enough.
> 
> Having a tmpfs filesystem for "/tmp" doesn't mean that a dedicated
> partition is required for "/tmp".

What you say doesn't work for me, but something else does.

Peace.
-- 
Paul E Condon           
pecondon@mesanetworks.net