DRINTERVAL

In my testing of HDR I noticed that with DRINTERVAL set to 0, on the primary server, top command shows oninit always running at the top. On this 2 CPU system 2 oninit processed takes around 48% of CPU even when the system is idle. It looks like some informix thread constantly checks for the log buffer to see whether any new update has been done to the database and if yes, send it to the secondary server. When DRINTERVAL is set to 1, and the system is idle, oninit process load almost disappears. The top command really shows that oninit is sitting idle. Does that mean that DRINTERVAL set to 0 is a performance killer.

It would be interested to know which threads are running that are consuming so much cpu (onstat -g act) and what are they doing (onstat -g stk <tid>). You could try some profiling of the oninit as well to gather more info. On the other hand maybe this cpu usage is not a bad sign. As long as when the real processing begins, whatever these threads are doing they don't interfere with the user threads and are scaled down to let the sqlexecs threads do their work.