On Fri, Sep 19, 2008 at 4:15 PM, Tres Seaver <tseaver@palladion.com> wrote:

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Marco Bizzarri wrote:

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Thanks for the suggestion, Tres, I'm trying it right now.

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I think this could be responsible for the problem I had a few months ago, under the name: "Asking advice on a Zope "stuck" (or: what did I do wrong?)"

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Do you think there will be some sort of "general" solution to the problem? I mean, the problem is actually that there are some objects which should not be ghostified, or am I wrong?

There are two problems here:

- Some objects need to be able to mark themselves as "sticky" for at least the duration of a transaction; my workaround is hackish, because if you omit the 'del conn._p_changed' it causes the object to be written needlessly; likewise, if the conn object *is* actually written to during the transaction, those changes will be discarded.

I'm afraid the workaround is not working for me; I've modified the test as follows: class DoubleTransactionTest(ZopeTestCase.ZopeTestCase): def _add_big_image(self, value, data): Image.manage_addFile(self.app, "f%06s" % value, data , "a title") def test_showdouble(self): manage_addZPsycopgConnection(self.app, "db_connection", "", "host=localhost user=postgres dbname=template1") self.app._setObject('sql', SQL.SQL("sql", "", "db_connection", "", "select * from pg_tables")) self.app.db_connection._p_changed = 1 self.app.sql() data = "*" * (1 << 20) for x in range(1000): self._add_big_image(x, data) print "Added %s " % x self.app.sql() But I can still see two transactions (I'm not bothering about removing the _p_changed flag, because this is a one shot test, just to see if it works... maybe I'm putting this in the wrong place).

- We need a way to keep the Pdata objects from evicting "precious" objects; ideally, Pdata instances would never be added to the cache at all. I worked a bit on a spike in which the Pdata iterator part would use a one-off connection with a zero-sized cache, but got stuck somewhere; maybe somebody else can make it work.

I would be glad to help, but my current understanding on "inner" Zope are not good enough (and my "free" time is even less ;))

Tres. - --

Do you mind if I forward this to ML? Regards Marco -- Marco Bizzarri http://notenotturne.blogspot.com/ http://iliveinpisa.blogspot.com/