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What is YGCT unit in jstat output

 S0C    S1C    S0U    S1U      EC       EU        OC         OU       MC     MU    CCSC   CCSU   YGC     YGCT    FGC    FGCT     GCT   
245760.0 245760.0 33804.8  0.0   1966080.0 364994.1 8028160.0   138003.6  25984.0 25429.9 2944.0 2877.2      8    0.451   2      0.153    0.603

This is the result. / jstat -gc pid 250ms 0 I want to know what is the unit of YGCT or FGCT? i.e. us or ms?

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This is the second place according to https://docs.oracle.com/javase/7/docs/technotes/tools/share/jstat.html .

Not explicitly stated, but it's easy to understand from the paragraph using the gcutil option:

The output of this example shows that the younger generation collection occurred between the 3rd and 4th samples. The collection took 0.001 seconds and moved the objects ...

0.001 is the difference between two consecutive YGCTs because it is a collection of the younger generation; search the paragraph from the link above to learn more about context.



Taking seconds as a unit for YGCT given that it would be illogical / confusing to have a different unit for FGCT than one might infer that seconds is also a unit for FGCT.

UPDATE

jstat for java 8 , jstat for java 9 , jstat for java 10, and jstat for java 11 all offer the same example, but with different values ​​than those mentioned here; see The collection took 0.078 seconds of a paragraph. I emphasize again that it is important to understand what the measurement of time (YGCT) is used for and why (because this is a collection of the younger generation).

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Unit of a second.

YGCT stands for Young Generation Garbage Collection Time



FGCT - means total garbage collection time

Both values ​​add up the time the GC takes for a particular task.

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