On Wed, 25 Mar 2009 15:24:47 +0100, Günter Obiltschnig <guenter.obiltsch...@appinf.com> wrote:
>Hi there, > >I have just upgraded SQLite in our application from 3.5.5 to 3.6.11 >(we are using the amalgamation), and I have noticed a sharp drop in >insert performance to more than half the speed that we had with 3.5.5. >We are using SQLite in an embedded Linux device, and the database >files are on a CompactFlash device. > >The inserts are being done into an initially empty table with 28 >columns, and all inserts (can be more than 100000) are done within one >large transaction, using a prepared insert statement. One additional >unique index on a single column is used on the table as well. Sounds good. >With 3.5.5, inserting 1000 rows into that table took about 7 seconds, >with 3.6.11 it takes 14-16 seconds. > >We are using PRAGMA synchronous = OFF and a cache size of 6000 pages. >The main reason why we updated was because we experienced memory >issues with 3.5.5. Reducing the cache size (PRAGMA cache_size) would >not release memory. > >Any ideas what causes this? Is the page_size the same in both cases? Does the page_size fit the I/O unity of the Compact Flash? (the default is not always optimal) For releasing cache memory, have a look at http://www.sqlite.org/c3ref/release_memory.html >Apart from that we are very happy with sqlite. A big thank you to >D. Richard Hipp and everyone who contributed to this great peace of >software. +1 >Thanks and best regards, > >Günter -- ( Kees Nuyt ) c[_] _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
