Linux Operating System Source Code: IBM Patches

The following patch originally by Martin Bligh exports some 
information about the buddy allocator.

Each column of numbers represents the number of pages of that order 
which are available.  In this case, there are 5 chunks of 
2^2*PAGE_SIZE available in ZONE_DMA, and 101 chunks of 2^4*PAGE_SIZE 
availble in ZONE_NORMAL, etc...  This information can give you a good 
idea about how fragmented memory is and give you a clue as to how big 
of an area you can safely allocate.

Node 0, zone      DMA      0      4      5      4      4      3 ...
Node 0, zone   Normal      1      0      0      1    101      8 ...
Node 0, zone  HighMem      2      0      0      1      1      0 ...