Description: new read balance for md raid1 code


Additional info:
* package version(s)
* config and/or log files etc.


Steps to reproduce:
get kernel 2.6.37 source, change the raid1.c and raid1.h code to new codes: check this email:
========================================================================================================
hi guys, i made some changes to md raid1 software, could centos test it? for me it work very nice =)
the raid1 new code is based in kernel 2.6.37
here is the new and old code:
www.spadim.com.br/raid1

just read_balance changed (4 modes: near_head(today) round_robin(counter per mirror) stripe (like raid0, with shift for make stripe less or more intensive), time based (depending on head positioning time and read size it calculate the fasted mirror, some new improvement must be done but it works, improvements= get io queue of each mirror and many a time estimation of queue time, with it get more close best disk)

it´s open source please help me testing it, neil at raid kernel must some benchmarks to put it inside kernel source
for mixed speed mirrors time based is good,
for ssd only round_Robin is good (per mirror count, put 230 for 230mb/s, 150 for mb/s or multiples to make a good round robin)
for disks and/or ssd mixed or not, stripe is good
for disks only near head is good