Hi Ron,
You are correct, the generation of class histograms take a long time.
The feature is enabled under the 'trace' level and should be used with
caution. The reason it takes so long time is that it is not
parallelized, so the whole heap is inspected by a single thread. To my
knowledge thi
going thru a gc-log of a box that had several Full-GCs (OpenJDK 64-Bit
Server VM (11.0.3+7-201905271830) on CentOS 6.9 with 20 cores and 132GB)
and i came across some really surprising times for the output from
-Xlog:gc*=info,gc+classhisto*=trace:
(notice the timestamps)
[2020-02-29T*02:39:42.403
