ADDITIONAL SYSTEM INFORMATION :
Linux 3.10.0-1062.4.3.el7.x86_64 #1 SMP Wed Nov 13 23:58:53 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux

openjdk version "17.0.3" 2022-04-19 LTS
OpenJDK Runtime Environment 21.9 (build 17.0.3+7-LTS)
OpenJDK 64-Bit Server VM 21.9 (build 17.0.3+7-LTS, mixed mode, sharing)


A DESCRIPTION OF THE PROBLEM :
The current NMT's output only dumps the current reserved/committed metrics for each category, while for categories like c2 compiler, the memory would be allocated and then freed in a quite short time, so it would be hard to notice spikes in such categories.

To make monitoring memory usage spikes easier, I propose to add a 'largest committed' metric to each category of NMT's output, just like ThreadPool's largestPoolSize(https://github.com/openjdk/jdk17/blob/74007890bb9a3fa3a65683a3f480e399f2b1a0b6/src/java.base/share/classes/java/util/concurrent/ThreadPoolExecutor.java#L484).