The Jstat command uses

Class Load Statistics:

[[Email protected]_app02 ~]$ jstat-class 2748Loaded  Bytes  Unloaded  Bytes     time    25120 53656.8      391   604.2      30.61Loaded: Load Class Bytes: Amount of space occupied unloaded: Quantity not loaded bytes: Footprint Not loaded time:

Compile statistics:

[[Email protected]_app02 ~]$ jstat-compiler 2748Compiled Failed Invalid   time   failedtype Failedmethod    2888      1       0    49.71          1 Sun/misc/urlclasspath getloader
Compiled: Number of compilations. Failed: Number of failures Invalid: quantity not available time: Failedtype: Failure Type Failedmethod: Failed method

　

Garbage Collection Statistics:

[[Email protected]_app02 ~]$ jstat-gc 2748 s0c    s1c    s0u    s1u      EC       EU        OC         OU       PC     PU    YGC     YGCT    FGC    fgct     GCT   1536.0 1536.0  0.0    0.0   1395200.0 597287.9 2796544.0   127364.1  159232.0 158879.9    2.236     27.093   29.329S0C: The size of the first surviving area s1c: The size of the second surviving area s0u: The use size of the first surviving area s1u: The size of the second surviving area EC: Sizes of the Garden of Eden EU: the use of the Eden Area OC: old age size OU: old age Use Size mc: Method Zone Size Mu: Method area use size C CSC: Compression class space size CCSU: Compression class space use size YGC: Young Generation garbage collection YGCT: Young generation garbage collection consumption time FGC: garbage collection times in the old age Fgct: garbage collection consumption time in the old age GCT: Total time spent on garbage collection

　　

Heap Memory Statistics:

[Email protected]_app02 ~]$ jstat-gccapacity 2748 ngcmn    ngcmx     NGC     s0c   s1c       EC      ogcmn      OGCMX       OGC         OC      pgcmn    pgcmx     PGC       PC     ygc    FGC 1398272.0 1398272.0 1398272.0 1536.0 1536.0 1395200.0  2796544.0  2796544.0  2796544.0  2796544.0  21504.0 2097152.0 159232.0 159232.0    69NGCMN: Cenozoic Minimum capacity ngcmx: Cenozoic Max capacity NGC: Current Cenozoic capacity s0c: The first surviving area size s1c: The size of the second surviving area EC: Size of the Eden District OGCMN: Old age Minimum Volume OGCMX: Old Age Max Volume OGC: Current old age size OC : Current old age size MCMN: Minimum metadata capacity MCMX: Maximum metadata capacity MC: Current metadata space size CCSMN: Minimum compression class space size Ccsmx: Maximum compression class space size CCSC: Current compression class space size YGC: Young generation GC number FGC: Number of GC times in the old age

　　

New Generation garbage Collection statistics:

[[Email protected]_app02 ~]$ jstat-gcnew 2748 s0c    s1c    s0u    s1u   TT MTT  DSS      EC       EU     YGC     ygct  1536.0 1536.0    0.0    0.0  1  1536.0 1395200.0 597717.6    2.236S0C: The first surviving area size s1c: The size of the second surviving area s0u: The use size of the first surviving area s1u: The use size of the second surviving area TT: The number of times the object survives in the Cenozoic MTT: The maximum number of times that an object survives in the Cenozoic DSS: Desired surviving Area size EC: The size of the Garden of Eden EU: the use of the Eden District size YGC: Young Generation garbage collection YGCT: Time spent by young generation garbage collection

　

Cenozoic Memory Statistics:

[Email protected]_app02 ~]$ jstat-gcnewcapacity 2748  ngcmn      ngcmx       NGC      s0cmx     s0c     S1CMX     s1c       ecmx        EC      ygc   FGC   1398272.0 1398272.0 1398272.0 465920.0 1536.0 465920.0   1536.0  1397248.0  1395200.0    69NGCMN: Cenozoic Minimum capacity ngcmx: Cenozoic Max capacity NGC: Current Cenozoic capacity S0CMX: Maximum surviving 1 zone size s0c: currently surviving 1 zone size S1CMX: Maximum surviving 2 zone size s1c: Currently surviving 2 area size ECMX: Max Eden area size EC: Current Eden District size YGC: Young Generation of garbage collection FGC: The number of recoveries in the old age

　　

Old age garbage Collection statistics:

[[Email protected]_app02 ~]$ jstat-gcold  2748   PC       PU        OC          OU       ygc    FGC    fgct     GCT   159232.0 158879.9   2796544.0    127364.1   27.093   29.329MC: Method Area Size Mu: Method area using size CCSC: Compressed class space size CCSU: Compression class space use size OC: old age size OU: old age use size YGC: Young Generation garbage collection FGC: Garbage collection times in the old age Fgct: garbage collection consumption time in the old age GCT: Total time spent on garbage collection

　　

Old Age Memory Statistics:

[[Email protected]_app02 ~]$ jstat-gcoldcapacity 2748   ogcmn       ogcmx        OGC         OC       ygc   FGC    FGCT     GCT     2796544.0   2796544.0   2796544.0   2796544.0   29.329OGCMN: The old Age minimum volume OGCMX: old age max capacity OGC: Current old age size OC: old age size YGC: Young Generation garbage collection times FGC: Garbage collection times in the old age Fgct: Garbage collection time spent in the old age GCT: Total time spent on garbage collection

　　

Meta Data Space Statistics:

[[Email protected]_app02 ~]$ jstat-gcmetacapacity 2748    mcmn       mcmx        MC       ccsmn      ccsmx     CCSC YGC   FGC    fgct     GCT   0.0    33152.0    33152.0        0.0        0.0        0.0     0    0.000    0.736 Note: This item needs to be MCMN on 1.8JDK: Minimum metadata capacity MCMX: Maximum metadata capacity MC: Current metadata space size CCSMN: Minimum compression class space size Ccsmx: Maximum compression class space size CCSC: Current compression class space size YGC: Young Generation garbage collection times FGC: Garbage collection times in the old age Fgct: Garbage collection time in the old age GCT: Total time spent on garbage collection

　　

Summarize garbage Collection statistics:

[[Email protected]_app02 ~]$ jstat-gcutil 2748  S0     S1     E      O      P     ygc     ygct    FGC    FGCT     GCT     0.00   0.00  42.88   4.55  99.78     -   2.236   29.329S0: Surviving zone 1 Current use ratio S1: Surviving 2 Zone current use ratio E: Eden area use ratio o: old age use ratio m: metadata area using proportional CCS: compression using proportional YGC: The number of garbage collection in the old Generation FGC: Garbage collection time in the old age FGCT: Waste recycling Total time Consumed

　　

JVM Compilation Method Statistics:

[[Email protected]_app02 ~]$ jstat-printcompilation 2748Compiled  Size  Type Method    2888   1072    1 Java/util/treemap fixafterdeletioncompiled: Number of recent compilation methods size: The number of bytecode for the most recently compiled method type: the compilation of the most recently compiled method. Method: Name identification.

　　

The Jstat command uses