"Fabio Durieux Lopes" <[EMAIL PROTECTED]> wrote: > > I've seen people saying one should use transactions.... > [B]ut my question is: If I'm using the same binary on > both computers shouldn't I get similar performances on > both computers? >
INSERT is very fast in SQLite. What is slow is not the INSERT but the implied COMMIT that occurs after each INSERT if you do not have an explicit transaction. The COMMIT does not return until all data has been safely written to the disk platter. This typically takes two complete rotations of the disk platter, which means you can do no more than about 60 COMMITs per second on your average computer. In contrast, you should be able to do 60000 INSERTs/second. SQLite uses the fsync() system call to make sure data has reached the disk before continuing. But fsync() is busted on some implementations. On some systems, fsync() is a no-op. This certainly makes it run a lot faster, but the downside is that the data does not necessarly reach the disk surface when SQLite thinks it does, and so if you lose power, your data might get corrupted. I have not heard of problems with fsync() on RHE3. But perhaps fsync() is disabled on that OS. Or perhaps fsync() is disabled by the particular disk controller you are using. Who knows. This is certain: By the laws of physics you cannot do more than about 60 transactions per second on a 7200 RPM disk drive. If you are seeing more than that, then something is wrong with your system and you will likely corrupt your databases if you lose power. -- D. Richard Hipp <[EMAIL PROTECTED]> ----------------------------------------------------------------------------- To unsubscribe, send email to [EMAIL PROTECTED] -----------------------------------------------------------------------------
