On Fri, 19 Mar 2021 11:49:39 GMT, Koichi Sakata <[email protected]> wrote:
> When a heap is used more than about 2.1GB, clhsdb jhisto shows a negative > number in the total field. > > $ java -Xmx20g Sample > > $ jhsdb clhsdb --pid 5773 > Attaching to process 5773, please wait... > hsdb> jhisto > ... > 299: 1 16 jdk.internal.misc.Unsafe > 300: 3402 10737610256 byte[] > Total : 15823 -2146661280 > Heap traversal took 1.793 seconds. > (Incidentally, the Sample is a program that only allocates many objects.) > > #### Details > This is because in ObjectHistogram class the totalSize variable is int type. > > The total size is the total of ObjectHistogramElement#getSize() and getSize() > returns long. So I changed int to long in the ObjectHistogram class. > > Additionally, I changed the type of the totalCount. This doesn't cause a bug, > but ObjectHistogramElement#getCount() also returns long. So it doesn't need > to treat it as int, I think. > > #### Tests > The jtreg test was successful. > $ sudo make run-test TEST=serviceability/sa/ClhsdbJhisto.java > > $ cat > build/linux-x86_64-server-fastdebug/test-results/jtreg_test_hotspot_jtreg_serviceability_sa_ClhsdbJhisto_java/text/summary.txt > serviceability/sa/ClhsdbJhisto.java Passed. Execution successful > > I confirmed the output with the same program. > > $ ./jdk/build/linux-x86_64-server-fastdebug/jdk/bin/java -Xmx20g Sample > $ ./jdk/build/linux-x86_64-server-fastdebug/jdk/bin/jhsdb clhsdb --pid 22463 > Attaching to process 22463, please wait... > hsdb> jhisto > > 300: 3410 19327547600 byte[] > Total : 16145 19328155080 > Heap traversal took 1.981 seconds. Marked as reviewed by kevinw (Committer). ------------- PR: https://git.openjdk.java.net/jdk/pull/3087
