just for my curiosity: what is thread A doing after/within the 100 seconds that elapsed in thread B after trying to get the exclusive transaction? maybe you simply forgot to finalize the query in thread A ?
> I understand what a deadlock is, and I know it's not technically a > deadlock. This is why I stated the title as deadlock behavior. > > Anyway, like I said, I can set the busy timeout to 100 seconds, and it > still hangs for 100 seconds, even though the queries being performed > by either thread should not take longer than a few millisecs at most. > > Any thoughts on my latest test with the begin exclusive method? > > On 4/8/09, Griggs, Donald <donald.gri...@allscripts.com> wrote: >> >> >> -----Original Message----- >> From: sqlite-users-boun...@sqlite.org >> [mailto:sqlite-users-boun...@sqlite.org] On Behalf Of Dave Brown >> Sent: Wednesday, April 08, 2009 1:16 PM >> To: General Discussion of SQLite Database >> Subject: Re: [sqlite] Strange sqlite_busy deadlock behavior >> >> I tried the BEGIN EXCLUSIVE method, but now the problem is that thread-A >> is in the middle of a query doing sqlite3_step() to get results, and >> thread-B tries a "begin exclusive" and gets back SQLITE_BUSY in the >> deadlock situation :) >> >> I guess I am forced to use your 2nd method?? >> >> ======================== >> ======================== >> Hi Dave, >> >> A *deadlock* would mean that neither process will ever proceed. >> http://en.wikipedia.org/wiki/Deadlock >> >> In your situation, Thread-B would simply wait until thread-A finishes >> --- either via some sort of inter-thread communication, or via polling >> on the part of thread-B. >> Thread-B experiences a delay, but no deadlock occurs. >> >> Presumably, thread-A is designed to "step lively" and not dally >> unnecessarily. >> >> Of course, the 2nd method is great if you have no concerns about >> isolation. >> ("PRAGMA read_uncommitted=ON") >> >> _______________________________________________ >> sqlite-users mailing list >> sqlite-users@sqlite.org >> http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users >> > _______________________________________________ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
