[Zope] Re: Stepper on Zope 2.9.X
Dennis Allison wrote: Chris others -- Anyone have experience with Stepper under Zope 2.8.X and Zope 2.9.X. It gets quite hammering under Zope 2.8.x on my current big project. I have a worry that there may be some silly bugs in the public release, but if you find any problems in 1.4.1, please let me know! Actually, just checked, there's a problem with continue_on_error in the released version, but I have a patch for that if you need to use it. I may, of course, just crank out a 1.4.2 with that fix in some time soon ;-) As for 2.9.x, nope, not been used by be, but I haven't heard of any problems either... cheers, Chris -- Simplistix - Content Management, Zope Python Consulting - http://www.simplistix.co.uk ___ Zope maillist - Zope@zope.org http://mail.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://mail.zope.org/mailman/listinfo/zope-announce http://mail.zope.org/mailman/listinfo/zope-dev )
[Zope] Re: Stepper on Zope 2.9.X
Thanks Chris. I'll be doing dsome experimentation and will let you know about any problems I find. -d On Sat, 18 Mar 2006, Chris Withers wrote: Dennis Allison wrote: Chris others -- Anyone have experience with Stepper under Zope 2.8.X and Zope 2.9.X. It gets quite hammering under Zope 2.8.x on my current big project. I have a worry that there may be some silly bugs in the public release, but if you find any problems in 1.4.1, please let me know! Actually, just checked, there's a problem with continue_on_error in the released version, but I have a patch for that if you need to use it. I may, of course, just crank out a 1.4.2 with that fix in some time soon ;-) As for 2.9.x, nope, not been used by be, but I haven't heard of any problems either... cheers, Chris -- ___ Zope maillist - Zope@zope.org http://mail.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://mail.zope.org/mailman/listinfo/zope-announce http://mail.zope.org/mailman/listinfo/zope-dev )
[Zope] Re: Stepper
Hi Gary, Gary Poster wrote: For our use case, the (quite frequent) cron kick could get to be very, very painful with long running tasks that may overlap (think *lots* of ConflictErrors). Ah well, if they're doing the same thing, just kicked off frequently, and you're worried about one run not finishing before another, I'd just put in some locking in Stepper that wouldn't run a chain/step if it was already running elsewhere, optionally logging this as an error... the pain carefully. I'm reasonably confident that Stepper would need to become a long running process with a queue in order to get there. I don't think it needs to be a long running process, and I think the queue could live elsewhere... Stepper is currently arguably better if you only have tasks like the ones you list, as long as you only start Stepper at a slow enough frequency that you have no chance for overlap (once a day sounds reasonable, though who knows). If you might overlap, zasync is safer ATM. The locking prevents overlap thing has worked really well for me in the past... zasync ended up being *very* careful, because we discovered we needed to be. Maybe a simpler, second gen design would need less care. I tend to prefer logging errors and failing as much as possible. Anything else means Stepper wouldhave to do guesswork and that would be bad... On the other hand, if you are interested in zasync's through-the- browser use case, maybe Stepper can grow a next-gen through-the-web API also. Nope, Stepper will never grow that. It's use case is much closer to that of zopectl run on steroids, but I think it could work well with a more light-weight zasync... cheers, Chris -- Simplistix - Content Management, Zope Python Consulting - http://www.simplistix.co.uk ___ Zope maillist - Zope@zope.org http://mail.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://mail.zope.org/mailman/listinfo/zope-announce http://mail.zope.org/mailman/listinfo/zope-dev )
[Zope] Re: Stepper
Hi Gary, Gary Poster wrote: Hey Chris. Ever on the lookout for better things to replace our code (e.g., zasync), I took a look at Stepper. It looks nice and simple (as per your company name, I suppose ;-). It's particularly nice that it looks easier to set up than zasync. Thanks! :-) I like things simple, hence the company name and tag line ;-) We primarily need zasync for frequent, user-requested async tasks fired from within a browser. From poking around in Stepper I thought maybe one could do that with a cron job kicking stepper and some other tricks, some other tricks being something in ZODB that built up a queue for a Stepper step to process... but it didn't seem that was a primary use case for you, because I still think zasync would do a better job there. Indeed, Stepper is for doing once a day type stuff. It was originally developed to run sets of migration code, but is now going to be used to do checking of Link Objects, sending reminders about expired content, packing ZODB, etc. That said, I see no reason why it couldn't be used to meet your use case... To be clear, Stepper does tasks zasync couldn't; oh? and I think it would be more appropriate for some of our zasync usages in the field, particularly once you beef up the error handling. I'm curious about this... what needs beefing up? The class design for defining jobs is certainly prettier than what I did too, though arguably both approaches have advantages. I might choose your approach for a new take on zope_exec plugin, for instance, if I did more zasync work. Hmmm, what's zope_exec? In any case, to your knowledge, am I on the right track with my analysis of what you have done? Yup, think so... Does Stepper support frequent, browser-requested async tasks, now or in your plans? Not really, that's not its focus. But, another product could easily be built to handle the put jobs in a queue thing and also supply a Stepper step. Maybe zasync could evolve to do just that and leave the actual offline task running (which is an admittedly pretty small task!) to Stepper? I would have sent this to the zope mailing list if I subscribed; feel free to cc responses there if you would like. Sure, I'll CC the zope list in for kicks :-) cheers, Chris -- Simplistix - Content Management, Zope Python Consulting - http://www.simplistix.co.uk ___ Zope maillist - Zope@zope.org http://mail.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://mail.zope.org/mailman/listinfo/zope-announce http://mail.zope.org/mailman/listinfo/zope-dev )
