cvs commit: src/sys/kern kern_mutex.c src/sys/conf NOTES options

[Robert Watson]

rwatson     2004-07-27 16:34:48 UTC

  FreeBSD src repository

  Modified files:
    sys/kern             kern_mutex.c 
    sys/conf             NOTES options 
  Log:
  Add "options ADAPTIVE_GIANT" which causes Giant to also be treated in
  an adaptive fashion when adaptive mutexes are enabled.  The theory
  behind non-adaptive Giant is that Giant will be held for long periods
  of time, and therefore spinning waiting on it is wasteful.  However,
  in MySQL benchmarks which are relatively Giant-free, running Giant
  adaptive makes an observable difference on SMP (5% transaction rate
  improvement).  As such, make adaptive behavior on Giant an option so
  it can be more widely benchmarked.
  
  Revision  Changes    Path
  1.1251    +6 -0      src/sys/conf/NOTES
  1.468     +1 -0      src/sys/conf/options
  1.145     +4 -0      src/sys/kern/kern_mutex.c