/tmp on tmpfs (was: Re: Summary/Minutes for today's FESCo meeting (2012-04-02))

[drago01]

On Mon, Apr 2, 2012 at 9:58 PM, Richard W.M. Jones <rjones at redhat.com> wrote:
> On Mon, Apr 02, 2012 at 08:32:56PM +0200, Miloslav Trmač wrote:
>> * #834 F18 Feature: /tmp on tmpfs -
>>   http://fedoraproject.org/wiki/Features/tmp-on-tmpfs  (mitr, 17:40:06)
>>   * AGREED: tmp-on-tmpfs is accepted (+5 -3)  (mitr, 18:12:52)
>
> Actually I think this is a good feature, but ...
>
> The feature page is wrong about "The user experience should barely
> change.  This is mostly a low-level change that has little visibility
> to the user."
>
> tmpfs is different in a number of important ways:
>
>  - it's very limited in space compared to a real disk

Which does not really matter in practice.

>  - it doesn't support O_DIRECT

Neither does this (which apps needs O_DIRECT on /tmp ? ).

>  - it doesn't support user extended attrs; and not very old kernels
>   didn't support any xattrs at all, meaning things like SELinux
>   labels don't work

Huh? Why would you run a "very old kernel" on fedora?

> All this means it's going to need a bit more testing, since
> potentially any package that stores a file on /tmp should be tested
> and may need to be fixed.

Sure if bugs are found they should be fixed. But note I have been
doing this testing for a *long* time (long as in years) on different
systems and yet have to find a package that breaks.