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Re: Local ECs (was Re: Can't modify EO objects! ARGH! =()
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Re: Local ECs (was Re: Can't modify EO objects! ARGH! =()


  • Subject: Re: Local ECs (was Re: Can't modify EO objects! ARGH! =()
  • From: Ben Trumbull <email@hidden>
  • Date: Wed, 23 Jul 2003 11:46:49 -0700

At 21:47 -1000 7/22/03, Art Isbell wrote:
Does this imply that EOF is now spawning notification threads? If not, how could an EC receive a notification at an unexpected time?

Any thread which performs EOF operations can post notifications. Additionally, each and every WOWorkerThread will invoke eventEnded on the delayed callback center after a request is finished.


The WOSessionTimeOut thread performs EOF operations, as does the JavaVM Finalizer thread.

"To ensure safe concurrent access to Enterprise Objects, it is your fundamental responsibility is to lock the Enterprise Objects you use directly."

Certainly, this level of clarity leaves something to be desired. Replace "Enterprise Objects" in that sentence with "objects from the EOF frameworks (e.g. ECs, OSCs, DBCs, etc)"


The same docs seem to imply that locking an EC will protect its objects from garbage collection and finalize threads which made no sense to me:

Don't infer so broadly from very precise language. All this implies is you are foobar if you don't lock correctly.


GC affects locking. Locking does not affect GC. The correct logic term for this relationship escapes me at the moment.

Is it correct that concurrent DB operations can occur *only* when multiple EOObjectStoreCoordinators have been configured?

Yes.

Extremely advanced developers doing work directly with the adaptors get a "Yes, but". Since I am unaware of any advantages here, multiple OSC are definitely the best approach.

Unfortunately, some of the behind-the-scenes complexity must be understood by developers. Apparently, significant behind-the-scenes changes have occurred with the WO 5.2 version

Well, the 5.2 delta doc does have sections on trivial subjects like memory management, multithreading, locking, and database operation concurrency.


File bugs on things which don't work the intuitive way.
--

-Ben
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 >Re: Local ECs (was Re: Can't modify EO objects! ARGH! =() (From: Art Isbell <email@hidden>)

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