I agree. This should be an option but we do not have it yet. Massimo
On Apr 2, 7:43 pm, Jonathan Lundell <jlund...@pobox.com> wrote: > On Apr 2, 2010, at 5:18 PM, mdipierro wrote: > > > the process that checks for the crontab runs but it does not spawns > > additional processes if nothing to do. > > Understood. But when it has something to do, if it's lightweight (like > expiring sessions), why run another process ever? > > I'm only talking about trivial tasks, but if you don't need cron > functionality for anything but trivial tasks.... > > > > > On Apr 2, 4:14 pm, Jonathan Lundell <jlund...@pobox.com> wrote: > >> On Apr 2, 2010, at 12:25 PM, AchipA wrote: > > >>> There was talk about this a few months back, and I even have a dev > >>> branch that does exactly this. There *are* some concerns, that's why I > >>> have not yet submitted that to Massimo until I resolve GIL/locking/etc > >>> issues. > > >> It also occurs to me that I can accomplish the same thing (though not > >> through crontab) by expiring sessions through a model file. Touch an empty > >> file in sessions/ to use as a timestamp, and when its mtime is more than > >> an hour old, run the expiry logic. > > >> BTW, does cron run if there's no crontab? > > >>> On Apr 2, 12:07 am, Jonathan Lundell <jlund...@pobox.com> wrote: > >>>> On Apr 1, 2010, at 11:20 AM, AchipA wrote: > > >>>>> Exactly, hardcron checks once a minute, softcron checks on each page > >>>>> load. The 'check' is calling a function or two and comparing a file's > >>>>> timestamp, so not *that* much more expensive. > > >>>> Thanks. > > >>>> In that case, I have a suggestion, perhaps not entirely thought out. If > >>>> cron is being used only for something relatively simple, say > >>>> expire_sessions.py, how about a kind of 'cron lite' that runs its tasks > >>>> in the context of an application rather than spawning an entirely new > >>>> instance of python+web2py to do the work? > > >>>> At the point where softcron is invoked, at the end of a request, if > >>>> we're running in litecron mode, process only the crontab file for the > >>>> current app, and run the cron tasks more or less as if they were models > >>>> (that is, exec in environment). > > >>>>> On Apr 1, 7:51 pm, Jonathan Lundell <jlund...@pobox.com> wrote: > >>>>>> On Apr 1, 2010, at 10:37 AM, AchipA wrote: > > >>>>>>> There is some overhead, but efficiency is a disputable term - there is > >>>>>>> certainly more overhead than hardcron, but IMO not in a way that would > >>>>>>> affect overall performance unless you're running it on a site that has > >>>>>>> hundreds of thousands of hits per day... > > >>>>>> Perhaps we could change (or eliminate) the wording. How about simply > >>>>>> 'Using softcron'? > > >>>>>> I'm curious: what is the extra overhead of soft vs hard cron? Just > >>>>>> that it does a test on each page access? I'm guessing that's pretty > >>>>>> cheap. > > >>>>>>> On Apr 1, 5:40 pm, Jonathan Lundell <jlund...@pobox.com> wrote: > >>>>>>>> Section 4.17 (cron) mentions hard vs soft cron defaults, but doesn't > >>>>>>>> say how to override them. > > >>>>>>>> Section 4.1 (cli) doesn't list --softcron > > >>>>>>>> The startup message for soft cron says: 'Using softcron (but this is > >>>>>>>> not very efficient)' > > >>>>>>>> In what sense "not efficient"? I understand that the timing is less > >>>>>>>> consistent, but is there really more overhead? softcron seems like a > >>>>>>>> pretty reasonable choice if all you're doing it deleting expired > >>>>>>>> sessions. -- You received this message because you are subscribed to the Google Groups "web2py-users" group. To post to this group, send email to web...@googlegroups.com. To unsubscribe from this group, send email to web2py+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/web2py?hl=en.
