VMARs are 24-byte records that describe virtual address space allocation, or reservation. They are located in a table in system memory. The principle use of the VMAR is to track the allocation of virtual memory, which may or may not be backed in RAM or on the SWAP file.
Arena records appear in a number of guises depending on the area storage they describe and whether the storage is shared, instance or private data. They are formatted by the KDB and DF .MA command. .MA takes either the handle or address or the VMAR as a parameter, or if no parameters are specified then the entire VMAR table is formatted.
# .ma har par cpg va flg next prev link hash hob hal 0001 %feeef020 00000100 %ff050000 001 001f 0002 0000 0000 0001 0000 =0000 0002 %feeef036 00000161 %feeef000 001 0001 0003 0000 0003 0002 0000 =0000 0003 %feeef04c 00001000 %fdeef000 001 0002 0021 0000 0000 0003 0000 =0000 0004 %feeef062 00000000 %60000000 003 05d3 0015 0000 0000 ffc0 0000 max=%fffc0000 0005 %feeef078 0000cc40 %04000000 007 0617 0072 0000 0000 fff0 0000 max=%1fff0000 0006 %feeef08e 00000003 %fff1b000 009 000f 03ad 0000 0000 0007 0000 sel=0100 0007 %feeef0a4 0000000c %ffe22000 009 0008 0019 0000 0000 0008 0000 sel=0400 0008 %feeef0ba 0000000d %ffe2e000 009 0009 0007 0000 0000 0009 0000 sel=1000 0009 %feeef0d0 00000010 %ffe3b000 009 01e2 0008 0000 0000 000a 0000 sel=0120 000a %feeef0e6 000001c1 %ac624000 121 002a 003a 0000 0000 000b 0000 =0000 000b %feeef0fc 00000006 %ffe4d000 009 000c 01df 0000 0000 000c 0000 sel=0130 000c %feeef112 00000003 %ffe53000 009 0094 000b 0000 0000 000d 0000 sel=0138 000d %feeef128 00000010 %11450000 379 0394 02d6 0000 0000 000e 0000 hco=00174 000e %feeef13e 00000001 %fff10000 001 03d3 0020 0000 0000 000f 0000 =0000 . . 00b6 %feeeffae 00000080 %00110000 169 03df 0076 0000 0000 041f 0000 hptda=03c9
The fields of principle interest are:
har
The right-hand column gives descriptive information about the use of the address range in a VMAR. Of particular interest are:
sel=ssss