Java HotSpot Virtual Machine

Hello,

I am new to profiling - sorry if this questions is trivial.

I run a test programm, with three threads (given as an example in a
java world article). The consumption of CPU time by the threads is
different because they have differen sleep-times. Ultimatly the method
"Math.atan" is called.

I start the VM with the "runhprof-option" "cpu=times". According to
the three threads I get three "Math.atan" entries in the "CPU TIME"
secition of the "java.hprof.txt" file. In the "self" and "accum"
columns of the three entries the following values show up:

self: 8.95% accum: 26.72%
self: 2.88% accum: 81.03%
self: 0.15% accum: 98.63%

The synopsis of the "java.hprof.txt" file says: "CPU TIMES
... measuring the time spent in individual methods (excluding the time
spent in callees)"

My interpretation of the findings and the synopsis is, that in the
"self" column the findings as described above are printed. But what
does the "accum:" column contain: "the time spent INCLUDING the time
spent in callees" would come to mind first, but than the relation of
the self and accum values should be the same for all three threads.

Can anyone tell me how to interpret the accum column.

Thanks in advance

Victor