We have a trace directly in the code to do this measurement. The problem is establishing the connection not the query itself.
It is when we call sqlite3_open16() after a simple debugging session with 3.7.13 it take the 1 sec and with 3.7.3 it is no wait at all! Any idea? Stéphane Léger, ing. Technical Specialist HMI Group Marine Control System L-3 MAPPS 514 787-4877 -----Original Message----- From: sqlite-users-boun...@sqlite.org [mailto:sqlite-users-boun...@sqlite.org] On Behalf Of Richard Hipp Sent: Wednesday, July 18, 2012 1:48 PM To: General Discussion of SQLite Database Subject: Re: [sqlite] Performance probleme between 3.7.3 and 3.7.13 On Wed, Jul 18, 2012 at 1:40 PM, <stephane.le...@l-3com.com> wrote: > Hi, > > > > We are updating the version of sqlite from 3.7.3 to 3.7.13 in our > software. But we are having a performance problem and I suspect a new > configuration but I don't know which one. I read on the site but > didn't find anything obvious. We use sqlite to store our graphical > page objects data. It generate very small amount of data but we have > between 100 and > 300 sqlite files to open and close. At initialisation of the software > we have to access all files to read some needed data. Doing it with > 3.7.3 take around 2 ms per file but with 3.7.13 it take 1.3 second for > the same call (select statement). > How are you making your timing measurements? What is your schema? What is the exact text of the query that is taking so much time? Have you run EXPLAIN QUERY PLAN on this schema to see if something has changed between 3.7.3 and 3.7.13? Have you tried running the suspect queries in an sqlite3.exe command-line shell to see how they perform there? Have you used APIs like sqlite3_stmt_status()<http://www.sqlite.org/c3ref/stmt_status.html>to see where SQLite is using its time? What else changed beside the SQLite core when you recompiled for 3.7.13? > > > > We are using : > > > > C++ (CppSQLite3 wrapper), ADO, Sqlite ODBC driver > > Window 7 64 bits but the application is 32 bits. > > > > The select is simple Select from PAGE where name = "aux_control" and > the result is always one row. > > > > My question what changes in SQLite can have this kind of impact on the > performance? > > > > Thanks for your help. > > > > Stéphane Léger, ing. > > Technical Specialist > > HMI Group > > Marine Control System > > L-3 MAPPS > > 514 787-4877 > > > > _______________________________________________ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > -- D. Richard Hipp d...@sqlite.org _______________________________________________ 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
