On 30 March 2012 19:36, Adrian Chadd <adr...@freebsd.org> wrote: > On 30 March 2012 10:56, Chris Rees <cr...@freebsd.org> wrote: >> On 30 March 2012 17:31, C. P. Ghost <cpgh...@cordula.ws> wrote: >>> On Fri, Mar 30, 2012 at 3:18 PM, <sth...@nethelp.no> wrote: >>>>> > However, if you always want to use tmpfs instead of stable storage, >>>>> please do not. Some people expect /tmp to be persistent. This is why >>>>> /etc/defaults/rc.conf has clear_tmp_enable="NO". Changing this would >>>>> break >>>>> the POLA. >>>>> > >>>>> This is a mistake. >>>>> >>>>> The default should be clear_tmp_enable="YES" >>>>> if only to uncover those broken configurations that expect /tmp to be >>>>> persistent. >>>> >>>> If you want to break POLA and make a lot of people angry, sure. >>>> Otherwise no. >>> >>> I couldn't agree more. Not clearing /tmp on reboot has been >>> the norm for way too long and it is too late to change now. >>> It's not just POLA, it also involves deleting data of unaware >>> users, and that should be avoided. >>> >>> Anyone willing to change policy w.r.t. /tmp can do so on their >>> own machines. Nothing is preventing them from doing so. >>> But by changing defaults, one should err on the side of >>> caution and remain conservative, IMHO. >> >> >From man hier: >> >> /tmp/ temporary files that are not guaranteed to persist across >> system reboots >> >> This assumption that people often make 'People will be astonished by >> this'-- I would like to have someone speak up and actually say "Yes, I >> use *temporary* directories for long-term storage" rather than the >> assumption that they are around. >> >> Software that assumes this should be fixed, and it won't be until the >> bug is exposed (I'll look at eaccelerator-- it probably should store >> its cache in /var/db). >> >> Maintaining the status quo because of some hypothetical scenario isn't >> really productive. >> > Let me tell you a story. > > Someone decided that ext4 could have a decent speed up if it > implemented the posix standard for not flushing files on close(). > After all, if you needed it to be guaranteed to be written to disk, > you would call a flush routine first, before you called close(). > > So they did this. > > Then people testing out ext4 discovered that upon crash, their > kde/gnome profiles were corrupted. > > Why? Because KDE/Gnome authors hadn't ever called flush before > close(), and they weren't the only ones. They didn't read the > standard, they only used the system and fixed bugs whenever their > system behaved against their expectations. They didn't notice that the > system was being different from the standard. > > Guess what ext4 did? :) > > Don't mis-estimate POLA.
Well, having thought about what this conversation was *really* about, I may have unintentionally derailed it a little. My original intention was to say to Oliver, please, don't be discouraged from using tmpfs for /tmp, and make sure you send PRs to the upstream of any programs that misbehave as such. Let's not make judgement on people who treat /tmp as persistent quite yet ;) Chris _______________________________________________ freebsd-current@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
