[ZODB-Dev] Transaction Manager Changes

[Jeremy Hylton]

>>>>> "TD" == Toby Dickenson <tdickenson@geminidataloggers.com> writes:

  TD> I am seeing some unusual behaviour in some classes which hook
  TD> into the transaction manager since Jeremy's sortKey changes. I
  TD> have not been able to reproduce a minimal test case yet, so this
  TD> has been diagnosed from activity logs on a production system.

  TD> The following two call sequences are ringing my alarm bells:

  TD> 1. abort, abort

  TD> 2. tpc_begin, abort, tpc_abort

  TD> Does this indicate a bug somewhere in the transaction manager,
  TD> or should my objects be expecting this?

  TD> (if it helps, there may be subtransactions involved too)

I don't have a good answer off the top of my head.  When I wrote the
first version of deadlock prevention code, I got a number of things
wrong in the subtransaction support.  I fixed everything that was
caught by the test suite.  If you see new failures in an application,
my first guess would be bugs in the code that weren't covered by the
test suite.

I'm not sure if I understand the problem report.  Are the call
sequences you report what is happening at the jar, e.g. the jar is
getting its abort() method call twice in a row?

Jeremy