On Sun, Nov 13, 2011 at 11:04:55AM +0000, Lars Wirzenius wrote: > On Sun, Nov 13, 2011 at 06:30:27PM +0800, Thomas Goirand wrote: > > Agreed. Anyway, I'd be happy to have, by policy, some hard limits > > We can discuss of a tolerable size, like 100M? Anyway, anything > > bigger than 512 MB is obviously abusing /tmp, IMHO. But if we're > > to have /tmp using tmpfs by default, it becomes really important > > to have such policy. > > The proper policy, IMHO, is that a) all software that uses temporary > files should obey TMPDIR if set (and fall back on /tmp if not) > and b) all software must deal with out-of-disk-space errors in a > sensible way (where the exact details may depend on the software).
Agreed. Software which has unusually large space requirements should, I think, make use of existing facilities such as statvfs(2) to check that sufficient free space exists prior to attempting to use several GiB. While not a guarantee of success, this would permit such applications to display a suitably informative error message, perhaps with instructions for rectifying the problem, rather than inconveniently failing later with ENOSPC. > It is then a sysadmin decision to setup /tmp or TMPDIR properly > so there's enough free space for temporary files for the software > they use. Debian should provide sensible defaults, but it's not > possible to pick defaults that are optimal for everyone, in > this situation. Given that MySQL, scientific software, and such > systems are mostly run on systems that have sysadmins, and desktops > are run by people who do not, it's sensible to favor the desktop > case by default. As mentioned in the original report, one of the "desktop" use cases is burning DVD images, which may require over 4 GiB in temporary space. Whether /tmp is suitable for such a purpose is IMO debatable. Currently, the size limits for /tmp and other temporary filesystems are set in /etc/default/tmpfs. It would I think be relatively simple for the debian-installer to change these default values according to the general usage of the system. This could also influence the automated partitioner should it be desirable to have a disc-backed /tmp. I would certainly like for the partitioner to permit changing of the mount defaults, including size limits, for the various tmpfses including /tmp, when generating the initial /etc/fstab. I lack the d-i knowledge to add support for tmpfs though. Regards, Roger -- .''`. Roger Leigh : :' : Debian GNU/Linux http://people.debian.org/~rleigh/ `. `' Printing on GNU/Linux? http://gutenprint.sourceforge.net/ `- GPG Public Key: 0x25BFB848 Please GPG sign your mail. -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/20111113124409.gy28...@codelibre.net
