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bcache on linux+gcc

Hi all, 

To set the record straight, I would like to report an interesting 
measurement on the effectiveness of the bcache module. While the
space overhead is very high on HP-UX 10.20 with native (som) 
compilers and linkers, on Linux wih gcc, the bcache module seems
to be doing handsomely. This measurement was taken with gdb4.17.86
on a Pentium Pro machine running Linux and gcc 2.7.2.3

Space taken to bring up gdb under gdb with bcache on  =  6+ Mb
                                      with bcache off = 16+ Mb
                                      %savings        = 62%

Here is some addition stats taken linux. See below for the same
stats on HP-UX.

Byte cache statistics for '/home/srikanth/binary/gdb/gdb':
==========================================================
Cache hits: 265581; Cache misses: 15559; Cache hit ratio: 94%
Space used for caching: 1214006 Space saved by cache hits: 6435194

Byte cache statistics for '/lib/libm.so.6':
==========================================

Cache hits: 25900   Cache misses: 1340  Cache hit ratio: 95%
Space used for caching: 494463;  Space saved by cache hits: 535452

Byte cache statistics for '/lib/libc.so.6':
===============================================

Cache hits: 250482 Cache misses: 6344 Cache hit ratio: 97%
Space used for caching: 857955 Space saved by cache hits: 5545239

Byte cache statistics for '/lib/ld-linux.so.2':
===============================================

Cache hits: 7502 Cache misses: 874 Cache hit ratio: 89%
Space used for caching: 498171 Space saved by cache hits: 166301


	See the consistently high cache hit ratio, in contrast to 
the low one on HP-UX.

Byte cache statistics for gdb:  (HP-UX)
==============================

Cache hits: 14088 Cache misses: 24986 Cache hit ratio: 36%
Space used for caching: 3965267 Space saved by cache hits: 174174

	I am not exactly certain why this should be the case, though
I wonder if this is due to there being a linker postprocessor pxdb 
on HP-UX, which eliminates duplicates from debug tables thereby
driving down the savings. Or this could be due to there being too
much debug info then again driving down savings. 

	May be the solution is to selectively turn it off HP-UX.
I'll dig deeper into this. 

Thanks 
Srikanth