On 2013-01-07, at 9:49 PM, Bradley Lucier lucier@math.purdue.edu wrote:
On Jan 6, 2013, at 5:41 PM, Marc Feeley wrote:
On 2013-01-06, at 1:17 PM, Bradley Lucier lucier@math.purdue.edu wrote:
I dismissed any differences that were < 20%.
Under that criteria, the new default did not lead to the best performance for dynamic, early, paraffins and nboyer, for which the old benchmarks setting of 10,000K minimum heap won.
The new default heap size beat the old benchmark setting of 10,000K minimum heap for cpstak, diviter, divrec, mbrot, sumfp, and string.
For no programs did the old default heap size beat the other settings.
Very nice.
Things are more complicated with this CPU:
model name : Intel(R) Xeon(R) CPU X5570 @ 2.93GHz
which has a 256KB level 2 cache, and an 8MB level 3 cache.
So the new default cache size is 4MB. I also tested with -m1 to get the old default.
You have to be careful with that intel processor type. On some versions of linux the system call that returns the size of the cache returns the wrong value. You might want to double check by explicitly calling (##processor-cache-size 0 0). If it returns 0 as I suspect, the minimal default heap size of 1 MB will be used, not 4 MB.
Marc