>From the article (thanks John), the magic is in "the "buddy" of each block 
can be found with an exclusive OR of the block's address and the block's 
size." 
Cool. 

Chip 



From:   "Roberts, John J" <[email protected]>
To:     [email protected]
Date:   10/22/2012 03:22 PM
Subject:        Re: Donald Knuth and The Art of Computer Programming - was 
RE: Book Enquiry
Sent by:        IBM Mainframe Discussion List <[email protected]>



Errr ???  I'm skeptical.  Suppose the address is 0, relative to the base 
of the managed storage pool.  What's its size?  Which is the buddy?

I may be a bit hazy on the details.  See 
http://en.wikipedia.org/wiki/Buddy_memory_allocation for something a bit 
more accurate.

What I am not hazy on is the performance boost we achieved by implementing 
a scheme with Knuth's algorithm at its core.  It cut the path length of a 
CICS GETMAIN or FREEMAIN from 2000+ instructions down to about 250.  And 
doubled the transactional capacity of our app.

John


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