"Daniel John Debrunner (JIRA)" <[EMAIL PROTECTED]> writes: > Also how can these methods take up 1.5% of system time, since they > are just modifying instance fields, isn't that all user code?
"Dyre Tjeldvoll (JIRA)" <[EMAIL PROTECTED]> writes: > Wrt. system cpu: I think that's strange too, but that is what the > profiler says. Maybe it is wrong. (it attributes the system cpu (and > most of the user cpu too) to the byte code line doing getfield #11, > which I think is ArrayInputStream.end I'm just guessing here, but embedded Derby should use very little system CPU (at least for read-only load, all data in page cache and only one client, which I assume is the configuration used). 1.5% of a number that is very small in the first place, is very close to nothing. Since this is some of the code that is executed most frequently, background noise might be accumulated there. I don't know what that background noise might be, but perhaps cache misses or involuntary context switches use system CPU? Does your profiler say how much of the total CPU time is system time? -- Knut Anders
