big holes in graphs

[frater]

Since I moved from 1.8.7 to the 1.9.x versions the graphs have big holes in them. It's as if not all the data is getting recorded.
All else seems to be running fine...

How can I check if I'm losing data?
I guess I need to query the database....

[richlv]

while the most common reason for that is performance problems, it might be something else as well. as a start, monitor busy rates of all internal processes and see whether any of them are notably busy.

of course, also check server logfile for any errors