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. > -- 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.
