Hash Tables of Buffers


 
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Old 06-09-2012
Question Hash Tables of Buffers

Hello,

I want to know how hash tables for buffers were implemented in Unix and now, in linux how they are implemented ?

I am aware of what hashing is..also quite familiar with Unix/Linux.

Special case is how device numbers comes into picture..I am curious !

If possible consider some example like there are 1000 buffers that can stay in buffer pool..
Please do not divert by proving it is of O(1). I know that. I am asking implementation thing!
 
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HASHER2(1)						    BSD General Commands Manual 						HASHER2(1)

NAME
hasher2 -- block based hashing utility SYNOPSIS
hasher2 [-hBrv] [-a algorithm] [-b size] [-s string] [-f from] [-t to] [[file] ...] DESCRIPTION
This program is part of the radare project. Hasher allows you to calculate, check and show the hash values of each block of a target file. The block size is 32768 bytes by default. It's allowed to hash from stdin using '-' as a target file. You can hash big files by hashing each block and later determine what part of it has been modified. Useful for filesystem analysis. This command can be used to calculate hashes of a certain part of a file or a command line passed string. This is the command used by the '#' command of radare. -a algo Select an algorithm for the hashing. Valid values are md5, crc32 and sha1 -b block size Define the block size -B Show per-block hash -s string Hash this string instead of using the 'source' and 'hash-file' arguments. -f from Start hashing at given address -t to Stop hashing at given address -r Show output in radare commands -v Show version information -h Show usage help message. SEE ALSO
radare2(1), rafind2(1), rahash2(1), rabin2(1), ranal2(1), radiff2(1), rasm2(1), ragg2(1), rarun2(1), rax2(1), AUTHORS
pancake <pancake@nopcode.org>, nibble <nibble@develsec.org> BSD
Mar 12, 2010 BSD