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BerkeleyStorage (was RE: [Zope-dev] ZODB and # of objects)
by Phillip J. Eby 22 Oct '99

22 Oct '99

At 10:04 AM 10/22/99 -0400, Michel Pelletier wrote: >> -----Original Message----- >> From: Andrew M. Kuchling [mailto:akuchlin@mems-exchange.org] >> Sent: Thursday, October 21, 1999 9:14 PM >> To: zope-dev(a)zope.org >> Subject: RE: [Zope-dev] ZODB and # of objects >> >> >> Michel Pelletier writes: >> >Are you using substransactions? If you are using 2.0.x, >> then you might >> >not notice any improvement with sub-transactions because of a >> >deactivation bug that was fixed just after the release >> (sigh). If you >> >> Trying the CVS version doesn't seem to help; I suspect that the >> problem is the growing in-memory index of FileStorage objects, and the >> fix is to use an alternate Storage class that scales better. > >Ty has the Berkely Storage, that might work quite well. > Keep in mind that this storage is still highly experimental, and also that it does not currently support Undo or Versions. (Although Ty might have Versions done in time for next week's Zope News... ;) ) But it does offer superior startup time to FileStorage for large databases and doesn't have the memory growth overhead that FileStorage does. On the other hand, BerkeleyStorage does *not* use temporary files for transaction logging, but keeps everything in memory until the transaction is committed, so if you have transactions involving large numbers of objects, Berkeley may not perform as well, memorywise. The long-term (i.e., a few weeks) plan for BerkeleyStorage is to support Undo, but only inside of Versions. We believe this will produce an ideal trade-off for applications where "run-time" activities would cause undue file-size growth under FileStorage, but where site maintainers/admins/content managers still need to have some undo capability. The other thing we'd like to do is figure out a way to have Versions manage conflicts optimistically, allowing non-versioned objects to be changed while a version is being worked on. This would allow tests of cataloging things, etc. without locking the catalog outside the version. ConflictError could then be raised on version commit if the appropriate transactions aren't undone. The undo data provided by the version could include indicators of which transactions involve objects which have been modified on the 'main line' and need to be undone for commit to occur. This is a bit more ambitious a project, as it would probably also require the ability to "revert" individual DB objects to their un-versioned state, independently of transactional undo, and/or to request a "hard" lock on an object.

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RE: [Zope-dev] ZODB and # of objects
by Michel Pelletier 22 Oct '99

22 Oct '99

> -----Original Message----- > From: Andrew M. Kuchling [mailto:akuchlin@mems-exchange.org] > Sent: Thursday, October 21, 1999 9:14 PM > To: zope-dev(a)zope.org > Subject: RE: [Zope-dev] ZODB and # of objects > > > Michel Pelletier writes: > >Are you using substransactions? If you are using 2.0.x, > then you might > >not notice any improvement with sub-transactions because of a > >deactivation bug that was fixed just after the release > (sigh). If you > > Trying the CVS version doesn't seem to help; I suspect that the > problem is the growing in-memory index of FileStorage objects, and the > fix is to use an alternate Storage class that scales better. Ty has the Berkely Storage, that might work quite well. -Michel

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RE: [Zope-dev] PTK Model
by Michel Pelletier 22 Oct '99

22 Oct '99

> -----Original Message----- > From: Patrick Phalen [mailto:zope@teleo.net] > Sent: Thursday, October 21, 1999 10:01 PM > To: zope-dev(a)zope.org > Subject: Re: [Zope-dev] PTK Model > > Seems to work fine in KFM (KDE) for Linux. I uploaded the style sheet. -Michel

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RE: [Zope-dev] PTK Model
by Michel Pelletier 22 Oct '99

22 Oct '99

> -----Original Message----- > From: Thilo Mezger [mailto:thilo@gonzo.innominate.local] > Sent: Friday, October 22, 1999 9:10 AM > To: zope-dev(a)zope.org > Subject: Re: [Zope-dev] PTK Model > > Michel Pelletier <michel(a)digicool.com> wrote: > > > Ok, we figured it out. If you generate the HTML on a Linux machine, > > they look aweful. If you generate it on a Windows machine, > they look > > normal. > > i think the GIF's are looking this aweful when being created on a > linux machine because the software couldn't render a scaled font > properly (or it's using a wrong one or is scaling a bitmap font or > something). maybe you can use a different font when creating the > GIF's ...? This is what I suspect. OD has a bunch of options for fonts, so I'll see if they do anything. I won't hold my breath. > about the missing style sheets file, just create an empty file and > then it will work without having to turn off style sheets in netscape. I uploaded the missing sheet. Thanks. > cheers > thilo

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Re: [Zope-dev] PTK Model
by Thilo Mezger 22 Oct '99

22 Oct '99

Michel Pelletier <michel(a)digicool.com> wrote: > Ok, we figured it out. If you generate the HTML on a Linux machine, > they look aweful. If you generate it on a Windows machine, they look > normal. i think the GIF's are looking this aweful when being created on a linux machine because the software couldn't render a scaled font properly (or it's using a wrong one or is scaling a bitmap font or something). maybe you can use a different font when creating the GIF's ...? about the missing style sheets file, just create an empty file and then it will work without having to turn off style sheets in netscape. cheers thilo -- mezger(a)innominate.de innominate AG networking people fon: +49.30.308806-11 fax: -77 web: http://innominate.de pgp: /pgp/tm

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Re: DTML Zclass ID bug - HELP!
by Alexandre Ratti 22 Oct '99

22 Oct '99

Thanks Toby. It works fine for me. I'll write up a short howto or a tip on this so that this information is readily available. Cheers. Alexandre At 12:00 21/10/1999 -0700, you wrote: >From: Toby Dickenson <tdickenson(a)geminidataloggers.com> >To: zope-dev(a)zope.org >Subject: RE: [Zope-dev] Re: DTML Zclass ID bug - HELP! >Date: Thu, 21 Oct 1999 10:01:17 +0100 >charset="iso-8859-1" > >You need to add the following setName call to the constructor... I'm not >sure whether this is a solution, or a hack. > > ><dtml-call "setName(REQUEST['id'])"> > > >-----Original Message----- > >Did anyone solve the problem describe by Anthony below ? > >I'd really like to know because it sounds suspiciously like one of my own >ZClass ailments: I can't access a ZClass instance ID and I can't display >its value on a property sheet.

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Event Triggers and Zope
by Ian Blenke 22 Oct '99

22 Oct '99

Is there a feasible way of triggering an event at some time in the future within the Zope model? The first workaround that comes to mind is an event "queue" Folder that would hold event objects (with associated date timestamps). Run a cron job alongside that triggers events via a simple "lynx -dump" of a method that walks the queue. Anyone else find this same need? - Ian C. Blenke <icblenke(a)2c2.com> <ian(a)blenke.com>

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PTK Model
by Michel Pelletier 22 Oct '99

22 Oct '99

Ok, here it is. http://www.digicool.com/michel/PTK/index.html ObjectDomain generated some pretty crappy diagram GIFs, there seems to be no way to control this behavior. <fuming..> Also, it seems that it doesn't work on Netscape for Linux (complains about a style sheet) but does work on MSIE5. Send me your bug reports. -Michel

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RE: [Zope-dev] ZODB and # of objects
by Michel Pelletier 22 Oct '99

22 Oct '99

> -----Original Message----- > From: Andrew M. Kuchling [mailto:akuchlin@mems-exchange.org] > Sent: Monday, September 27, 1999 7:29 PM > To: zope-dev(a)zope.org > Subject: [Zope-dev] ZODB and # of objects > > FileStorage's property of requiring memory proportional to the number > of objects in the ZODB may be causing me problems. I'm running into > trouble with a ceiling of 150,000 items, but the memory usage becomes > too high, 60 or 70 or 80Mb well before reaching that point. I don't > think the problem is a memory leak in my code, but perhaps I'm doing > something wrong; has anyone stored that many items in a ZODB before? > What was the memory usage like? Are you using substransactions? If you are using 2.0.x, then you might not notice any improvement with sub-transactions because of a deactivation bug that was fixed just after the release (sigh). If you use the CVS version and tune your cache agressively, you should be able to keep the memory below a ceiling for any number of objects. ZCatalog is pretty agressive about this, not only does it sub-transact but it also kicks the cache with self._p_jar.cacheFullSweep(1). > (The largest number of objects stored in a Zope database would > be an interesting bit of trivia.) Theoretically, 2^64. -Michel

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RE: [Zope-dev] PTK Model
by Michel Pelletier 21 Oct '99

21 Oct '99

> -----Original Message----- > From: Andrew M. Kuchling [mailto:akuchlin@mems-exchange.org] > Sent: Thursday, October 21, 1999 4:46 PM > To: 'zope-dev(a)zope.org' > Subject: Re: [Zope-dev] PTK Model > > Disabling style sheets makes it display; when Netscape can't find a > style sheet, the 404 error displays the style sheet link. Everything > seems to display fine with style sheets disabled. (I see what you > mean by poor diagrams, though; yikes!) Ok, we figured it out. If you generate the HTML on a Linux machine, they look aweful. If you generate it on a Windows machine, they look normal. Good thing Java is cross platform, otherwise we all might actually get something done in life. -Michel

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