Occasional long insert time with hard, real-time application (1 reply)

I'm using MySQl in a fairly hard, real-time application. The insertions into the Database normally take about 4 seconds. If I run a test over-night, about 6 out of 20,000 insertions take as much as 20 Seconds.

Is this expected? Is it possible for MySQL to support a hard, real-time application without occasional excessive insert times?

Many thanks!