Re: 2.5.57 IO slowdown with CONFIG_PREEMPT enabled

[Robert Macaulay]

On Wed, 15 Jan 2003, Andrew Morton wrote:
> OK, thanks.  The below patch reverts the spinlocking change,
> if you could please test that with CONFIG_PREEMPT=y

Reverting that brings the speed back up
2.5.57, preempt on, 8gig RAM
 r  b   swpd   free   buff  cache   si   so    bi    bo   in    cs us sy 
id wa
 5  1   3624   7832 177824 7413824    0    1    16  8195  156   153  0 48 
46  5
 8  0   3624   7124 179336 7413612    0    0     0 110510 1317  2014  0 83 
10  7
 9  1   3624   8112 182552 7409316    0    1     0 109681 1309  1369  0 90  
4  6
 8  1   3624   8176 185824 7405948    0    0     0 112612 1302  2202  0 75 
17  8
10  1   3632   7328 189300 7402564    0    1     0 112160 1352  1764  0 81 
12  6