Thanks for the reply. We debugged the sqlite structure when we encounter the issue, and we do not see any open transactions (no initialized vdbe) and still see that the shared_lock is set by the pager. Is there anything obvious that we are missing. I can paste the gdb results for the various sqlite structure if that helps.
Thanks in advance Jay A. Kreibich-2 wrote: > > On Tue, Mar 01, 2011 at 12:20:32PM -0800, mmudi scratched on the wall: >> >> We are using sqlite version 3.3.17 in a production environment, and are >> facing an issue where a particular process is not releasing the read lock >> on >> the sql file. This locks up the database when any write operations are >> attempted by other processes. The process under question is not multi >> threaded and stack trace reveals that the process is not stuck in an >> SQLite >> library call but is processing other requests. >> >> A code review of the DB access API has not revealed any resources or >> calls >> that have not been closed/freed properly. > > This can be verified by attempting to close the database connection. > If there are still unresolved statements, an error will be returned. > > Additionally, you must actually call _reset() or _finalized() on a > statement, even if it is run until _step() returns SQLITE_DONE. In > some cases, in some versions of SQLite, the locks are not released > until the statement is actually reset/finalized. > >> Questions >> -- >> From my debugging efforts, the issue appears to be that the process >> entered >> the sqlite library at some point in its operation, acquired a read lock, >> and >> returned from the library, but failed to release the read lock. Under >> what >> circumstances can this occur? > > Many. But if you're correctly resetting all your statements, the > most likely cause is an SQL "BEGIN" was issued without a > corresponding "COMMIT" or "ROLLBACK." > > -j > > -- > Jay A. Kreibich < J A Y @ K R E I B I.C H > > > "Intelligence is like underwear: it is important that you have it, > but showing it to the wrong people has the tendency to make them > feel uncomfortable." -- Angela Johnson > _______________________________________________ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > > -- View this message in context: http://old.nabble.com/Read-Lock-not-released..-tp31043990p31168820.html Sent from the SQLite mailing list archive at Nabble.com. _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
