RFR: 7463: JfrEditor instances are kept in memory by NavigationHistory

Tue Nov 30 11:04:33 UTC 2021

Provide a sub class of NavigationHistory instead of implementing a
full INavigationHistory.
JfrEditor is not kept anymore when releasing state/disposing.

JMC 8.1, opening 13 recordings, then closing them:

COMP11909:~/git/jmc-jpbempel$ jcmd 55089 GC.heap_info
55089:
 garbage-first heap   total 989184K, used 488772K [0x0000000700000000, 0x0000000800000000)
  region size 1024K, 1 young (1024K), 0 survivors (0K)
 Metaspace       used 60486K, capacity 65423K, committed 65584K, reserved 1105920K
  class space    used 6822K, capacity 8453K, committed 8576K, reserved 1048576K
COMP11909:~/git/jmc-jpbempel$ jcmd 55089 GC.run
55089:
Command executed successfully
COMP11909:~/git/jmc-jpbempel$ jcmd 55089 GC.heap_info
55089:
 garbage-first heap   total 989184K, used 488410K [0x0000000700000000, 0x0000000800000000)
  region size 1024K, 1 young (1024K), 0 survivors (0K)
 Metaspace       used 61621K, capacity 66457K, committed 66736K, reserved 1107968K
  class space    used 6938K, capacity 8583K, committed 8704K, reserved 1048576K

memory is not released even after GC

JMC 8.2 + fix:

COMP11909:~/git/jmc-jpbempel$ jcmd 56259 GC.heap_info
56259:
 garbage-first heap   total 1625088K, used 556392K [0x0000000700000000, 0x0000000800000000)
  region size 1024K, 1 young (1024K), 0 survivors (0K)
 Metaspace       used 61931K, capacity 66724K, committed 66992K, reserved 1107968K
  class space    used 6991K, capacity 8586K, committed 8704K, reserved 1048576K
COMP11909:~/git/jmc-jpbempel$ jcmd 56259 GC.run
56259:
Command executed successfully
COMP11909:~/git/jmc-jpbempel$ jcmd 56259 GC.heap_info
56259:
 garbage-first heap   total 109568K, used 28592K [0x0000000700000000, 0x0000000800000000)
  region size 1024K, 1 young (1024K), 0 survivors (0K)
 Metaspace       used 62269K, capacity 67053K, committed 67248K, reserved 1107968K
  class space    used 6994K, capacity 8588K, committed 8704K, reserved 1048576K

-------------

Commit messages:
 - 7463: JfrEditor instances are kept in memory by NavigationHistory

Changes: https://git.openjdk.java.net/jmc/pull/338/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jmc&pr=338&range=00
  Issue: https://bugs.openjdk.java.net/browse/JMC-7463
  Stats: 44 lines in 2 files changed: 2 ins; 32 del; 10 mod
  Patch: https://git.openjdk.java.net/jmc/pull/338.diff
  Fetch: git fetch https://git.openjdk.java.net/jmc pull/338/head:pull/338

PR: https://git.openjdk.java.net/jmc/pull/338