问题
There are two items called CGC and CGCT. I cannot found the documention and man page describing their meaning.
# jstat -gc 139934
S0C S1C S0U S1U EC EU OC OU MC MU CCSC CCSU YGC YGCT FGC FGCT CGC CGCT GCT
0.0 15360.0 0.0 15360.0 113664.0 9216.0 88064.0 23552.0 82304.0 80084.2 10112.0 9360.4 10 0.157 0 0.000 6 0.018 0.175
# java -version
openjdk version "11.0.2" 2019-01-15 LTS
OpenJDK Runtime Environment Corretto-11.0.2.9.3 (build 11.0.2+9-LTS)
OpenJDK 64-Bit Server VM Corretto-11.0.2.9.3 (build 11.0.2+9-LTS, mixed mode
I used the default jvm arguments.
#jhsdb jmap --heap --pid 139934 | grep GC
Garbage-First (G1) GC with 13 thread(s)
回答1:
As far as I understand from this link, the first C
in CGC
and CGCT
stands for "concurrent", so based on the description from the docs for GC
and GCT
:
GCT: Total garbage collection time.
I would say CGTC
is "Concurrent Total Garbage Collection" and CGC
is "Concurrent Garbage Collection".
来源:https://stackoverflow.com/questions/55803602/whats-the-meaning-of-cgc-and-cgct-in-jdk11-jstat-gc-pid