Re: gp-2.15.3 compiled on Ubuntu on AMD 7600X very slow compared to i7 (many page faults), Win11 gp-2.15.3 on 7600X better than i7. How to fix AMD Ubuntu?

[hermann@stamm-wilbrandt.de]

On 2023-06-26 20:18, Bill Allombert wrote:
> Do you have the same version of GNU MP on both systems ?
Yes (6.2.1).

> Did you compile PARI with pthread support ?
No, just "make" as stated in INSTALL.

All problems were gone after installing Ubuntu 22.04 (this time desktop 
and not server) on fast new SSD.
I updated PARI/GP section, and separated old section with problem for 
history with reference:
https://github.com/Hermann-SW/7600X#parigp

So cool, now "7600X / i7-11850H" runtime percentages for 100,355-digit 
prime are 86.4% for PARI/GP and 84.6% for C++ with libgmpxx. Even 
better, running 6x gp in parallel without doing anything else shows 6 
times the same runtime!


All these numbers are when running with DDR5-4800 RAM, which seems not 
to allow for PBO (Performance Boost Optimization, 7600X can do 5300MHz 
in Turbo mode instead of 4700MHz). Today I received Crucial 16GB 
DDR5-5600 RAM (for 49€ or 53.50$). I hope this will allow me to run 
7600X at 5300MHz (or more) for achieving 4,221 Thread Mark (rank 18 in 
https://www.cpubenchmark.net/singleThread.html) compared to 3,690 
measured with DDR5-4800 RAM I used until now.


Btw, while building I did "make bench".
Is there some place with results for different CPUs?
This seems to be fast ...

hermann@7600x:~/Downloads/pari-2.15.3$ make bench
Making bench in Olinux-x86_64
make[1]: Entering directory 
'/home/hermann/Downloads/pari-2.15.3/Olinux-x86_64'
* Testing objets           gp-sta..TIME=    1   gp-dyn..TIME=    1
* Testing analyz           gp-sta..TIME=    5   gp-dyn..TIME=    1
* Testing number           gp-sta..TIME=    4   gp-dyn..TIME=    6
* Testing polyser          gp-sta..TIME=    2   gp-dyn..TIME=    2
* Testing linear           gp-sta..TIME=    2   gp-dyn..TIME=    2
* Testing elliptic         gp-sta..TIME=    7   gp-dyn..TIME=    7
* Testing sumiter          gp-sta..TIME=    2   gp-dyn..TIME=    3
* Testing graph            gp-sta..TIME=    1   gp-dyn..TIME=    2
* Testing program          gp-sta..TIME=    2   gp-dyn..TIME=    2
* Testing trans            gp-sta..TIME=    2   gp-dyn..TIME=    3
* Testing nfields          gp-sta..TIME=   20   gp-dyn..TIME=   18
+++ Total bench for gp-sta is 32
+++ Total bench for gp-dyn is 32
make[1]: Leaving directory 
'/home/hermann/Downloads/pari-2.15.3/Olinux-x86_64'
hermann@7600x:~/Downloads/pari-2.15.3$



Regards,

Hermann.