Action required: Rawhide: /tmp is now on tmpfs

[Brian Wheeler]

On 06/01/2012 10:23 AM, Alexey I. Froloff wrote:
> On Fri, Jun 01, 2012 at 09:27:16AM -0400, Brian Wheeler wrote:
>>> my biggest problem was that tmpfs by
>>> default allocates half of physical RAM for partition.  So I just
>>> allocated big enough swap and added a line to /etc/fstab with
>>> appropriate size= option.
>> And how is a random user supposed to know this?
> In Soviet ALT Linux we didn't care about "random users" ;-)
So that means that "random users care about YOU!"

> In perfect world "random user" must be smart enough to read the
> documentation.  However, this implies, that such documentation
> exists and easily accessed (which at first sight is true for
> Fedora).

Sure.  When there's "mystery" problems , who is going to think "oh yeah, 
/tmp is in ram now and chrome just wrote a big temp file...better go 
look up how to add swap"?  I'm going to guess 'nearly nobody'

>> So if things start acting up the answer is to add more swap and
>> mess with fstab?  WTF?
> This is up to Release Managers.  Reasonable defaults in
> installer, documentation, etc...
>

The thing is, the amount of "reasonable" swap is now not a function of 
just RAM overflow but also /tmp usage -- which is something that can 
vary dramatically at runtime.

>> So now any software which uses /tmp for *gasp* temporary space
>> is now potentially broken depending on the size of the
>> temporary data.
> Well, no software should use /tmp directly, IMO.  There's nice
> environment variable $TMPDIR.  You can always point it to
> $HOME/tmp for example.  And you can always turn it off if you
> really need to.

Sure, no software _should_ use it directly, but it happens a lot...and 
not in packages which are in the repo:  home grown and third party.   
Additionally, there's 20+ years of habit to break for a lot of people 
and that's not something you can easily patch.  Running things like 
"grep \"\ 404\  apache.log > /tmp/404s.log" is pretty ingrained for many 
people.

I'll probably turn it off because I've been down this road with Solaris 
and it sucked.  I will grant that the linux implementation is better, 
but I want RAM to be used for the running software and if its not being 
used for that, caching what's actively being used.

>> Sorry guys, this feature sucks.
> I like this feature, and there should be easy, well documented
> way to turn it off.  I personally don't see a reason why it
> should be off by default.
>

Well, since I'm probably going to turn it off, can someone give me a 
good reason why it should be turned _on_ by default?  For me, the 
"Benefit to Fedora" bullets are not compelling.