Hi guys, I just wanted to check in and see if there was any news. Holger's suggestion about using the "with lock exclusive" clause does seems to workaround the issue. But I would still be interested in hearing more about what's going on.
Thanks, Mark On Mon, 2003-01-13 at 16:04, Mark Wong wrote: > I have a scenerio in SAP DB 7.4.3.7 (and I believe it'll happen on 7.3 > also) on Linux where four users appear to be deadlocked. It takes at > least 4 users to make this case happen reliably and quickly. I have a > table with a single column and a single row, where a stored procedure > will select the row from the table and then update it. The stored > procedure is execute with repeatable reads. > > Here are a couple of snapshots from the LOCKSTATISTICS table when this > deadlock-like behavior is occuring. > > dbmcli on DBT2>sql_execute select * from lockstatistics > OK > END > 604;' 6010';0;'';55;'DBT';'20030113';'00220458';'';' > >4970';(null);(null);(null);'row_exclusive';'write';1369;'cl004.pdx.osdl.net';'DBT';'B';'';9;'';'x'FFFE000000000001'' > 605;' 6011';0;'';80;'DBT';'20030113';'00220459';'';' > >4970';(null);(null);(null);'row_exclusive';'write';1370;'cl004.pdx.osdl.net';'DBT';'B';'';9;'';'x'FFFE000000000001'' > 606;' 6013';0;'';56;'DBT';'20030113';'00220500';'';' > >4970';(null);(null);(null);'row_exclusive';'write';1373;'cl004.pdx.osdl.net';'DBT';'B';'';9;'';'x'FFFE000000000001'' > 607;' 6008';0;'';81;'DBT';'20030113';'00220501';'';' > >4970';(null);'row_share';(null);'row_exclusive';'write';1376;'cl004.pdx.osdl.net';'DBT';'B';'';9;'';'x'FFFE000000000001'' > > --- > dbmcli on DBT2>sql_execute select * from lockstatistics > OK > END > 604;' 6010';0;'';55;'DBT';'20030113';'00220458';'';' > >4940';(null);(null);(null);'row_exclusive';'write';1369;'cl004.pdx.osdl.net';'DBT';'B';'';9;'';'x'FFFE000000000001'' > 605;' 6011';0;'';80;'DBT';'20030113';'00220459';'';' > >4940';(null);(null);(null);'row_exclusive';'write';1370;'cl004.pdx.osdl.net';'DBT';'B';'';9;'';'x'FFFE000000000001'' > 606;' 6013';0;'';56;'DBT';'20030113';'00220500';'';' > >4940';(null);(null);(null);'row_exclusive';'write';1373;'cl004.pdx.osdl.net';'DBT';'B';'';9;'';'x'FFFE000000000001'' > 607;' 6008';0;'';81;'DBT';'20030113';'00220501';'';' > >4940';(null);'row_share';(null);'row_exclusive';'write';1376;'cl004.pdx.osdl.net';'DBT';'B';'';9;'';'x'FFFE000000000001'' > > --- > > > The source code and table creation and population script can be > retrieved from: > > http://www.osdl.org/archive/markw/lock_test/lock_test.tar.gz > > It's a multi-processed odbc application. It can be built simply by > typing make, and the program is execute with: > > sqlmef2 -d dbt2 -t 4 > > with -d <connect string> and -t <number of processes> > > A trace of my test can be retrieved from: > > http://www.osdl.org/archive/markw/lock_test/lock_test.out.gz > > Let me know if there any more information I can provide. > > Thanks! -- Mark Wong - - [EMAIL PROTECTED] Open Source Development Lab Inc - A non-profit corporation 15275 SW Koll Parkway - Suite H - Beaverton OR, 97006 (503)-626-2455 x 32 (office) (503)-626-2436 (fax) http://www.osdl.org/archive/markw/ _______________________________________________ sapdb.general mailing list [EMAIL PROTECTED] http://listserv.sap.com/mailman/listinfo/sapdb.general
