Storage Management (MEMINFO)

The MEMINFO section provides information about the Memory Manager.

See Using the Metronome Garbage Collector for details about how the memory manager component works.

This part of the Javadump gives various storage management values (in hexadecimal), including the free space and current size of the heap. It also contains garbage collection history data, described in Default memory management tracing. Garbage collection history data is shown as a sequence of tracepoints, each with a timestamp, ordered with the most recent tracepoint first.

Javadumps produced by the standard JVM contain a "GC History" section. This information is not contained in Javadumps produced when using the Real Time JVM. Use the -verbose:gc option or the JVM snap trace to obtain information about GC behavior. See Using verbose:gc information and Snap traces for more details.

The following example shows some typical output. All the values are output as hexadecimal values.

0SECTION       MEMINFO subcomponent dump routine
NULL           =================================
NULL           
1STMEMTYPE     Object Memory
NULL           region     start      end        size       name
1STHEAP        0x080FA804 0xF2CE0000 0xF6CD0000 0x03FF0000 Default 
NULL
1STMEMUSAGE    Total memory available: 67108864 (0x04000000)
1STMEMUSAGE    Total memory in use:    01344960 (0x001485C0)
1STMEMUSAGE    Total memory free:      65763904 (0x03EB7A40)
NULL
1STSEGTYPE     Internal Memory
NULL           segment    start      alloc      end        type       size
1STSEGMENT     0x080F7530 0x0820A008 0x0820A008 0x0821A008 0x01000040 0x00010000
1STSEGMENT     0x080F7588 0x08302E48 0x08302E48 0x08312E48 0x01000040 0x00010000
1STSEGMENT     0x080F75E0 0x0827CCF8 0x0827CCF8 0x0828CCF8 0x01000040 0x00010000
1STSEGMENT     0x082DC9D0 0x08342E68 0x08342E68 0x08352E68 0x01000040 0x00010000
<< lines removed for clarity >>

NULL
1STSEGUSAGE    Total memory available: 00611268 (0x000953C4)
1STSEGUSAGE    Total memory in use:    00000000 (0x00000000)
1STSEGUSAGE    Total memory free:      00611268 (0x000953C4)
NULL           
1STSEGTYPE     Class Memory
NULL           segment    start      alloc      end        type       size
1STSEGMENT     0xF29B7CB0 0xF24890C8 0xF248A040 0xF24910C8 0x00010040 0x00008008
1STSEGMENT     0xF29B7C58 0xF2568008 0xF256B868 0xF2588008 0x00020040 0x00020000
1STSEGMENT     0xF29B7C00 0xF29BBD60 0xF29C27B8 0xF29C3D60 0x00010040 0x00008008
1STSEGMENT     0xF29B7BA8 0xF25DC008 0xF25F4A98 0xF25FC008 0x00020040 0x00020000
<< lines removed for clarity >>

NULL
1STSEGUSAGE    Total memory available: 01804756 (0x001B89D4)
1STSEGUSAGE    Total memory in use:    01542116 (0x001787E4)
1STSEGUSAGE    Total memory free:      00262640 (0x000401F0)
NULL           
1STSEGTYPE     JIT Code Cache
NULL           segment    start      alloc      end        type       size
1STSEGMENT     0x0815B0B8 0xF2B71000 0xF2BF1000 0xF2BF1000 0x00000068 0x00080020
NULL
1STSEGUSAGE    Total memory available: 00524320 (0x00080020)
1STSEGUSAGE    Total memory in use:    00524288 (0x00080000)
1STSEGUSAGE    Total memory free:      00000032 (0x00000020)
NULL           
1STSEGTYPE     JIT Data Cache
NULL           segment    start      alloc      end        type       size
1STSEGMENT     0x0815B258 0xF2AF0008 0xF2AFB818 0xF2B70008 0x00000048 0x00080000
NULL
1STSEGUSAGE    Total memory available: 00524288 (0x00080000)
1STSEGUSAGE    Total memory in use:    00047120 (0x0000B810)
1STSEGUSAGE    Total memory free:      00477168 (0x000747F0)


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