View Single Post
Old 2020-11-30, 18:54   #62
pvn
 
Nov 2020

22 Posts
Default

I just built v19 and I'm fairly new to the Arm universe. I am poking around on some of the AWS EC2 instances with "graviton" processors. I notice that if I run with 4 cores, using a command line like this:


Code:
#  ./Mlucas -s m -cpu 0:3

then I get this message in the output quite a bit:


Code:
mers_mod_square: radix0/2 not exactly divisible by NTHREADS - This will hurt performance.

and, sure enough, runs with four cores tend to be (much) slower than 2 cores or even 1 core on the same instance. is there something I should be doing differently?
pvn is offline   Reply With Quote