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]

I bought new not-too-expensive big single thread performance PC with AMD 
Ryzen 7600X CPU for factoring big numbers / number theory:
https://github.com/Hermann-SW/7600X#7600x

I used C++ with libgmpx executables to determine "sqrt(-1) (mod p)" for 
10,000-/36,401-/100,355-digit primes.
7600X runtimes measured were 10%+ better for 7600X compared to 
i7-11850H, matching PassMark single thread numbers (no PBO yet, 
Performance Boost Optimization):
https://github.com/Hermann-SW/7600X#c-with-libgmpxx

Win11 was preinstalled, so I installed Ubuntu 22.04 server on other disk 
in parallel, allowing same hardware+bios comparisons.
While 7600X Win11 gp-1.25.3 is a bit faster with GP scripts (determining 
same numbers as with C++) than i7, 7600X Ubuntu numbers are much worse 
than i7-11850H numbers:
https://github.com/Hermann-SW/7600X#parigp

I compiled gp-2.15.3 sources on i7 and 7600X the same, following 
instructions in INSTALL.
Reason for the bad 7600X Ubunto runtimes seems to be the many page 
faults seen with "perf stat".

Is there something I need to do additionally when compiling PARI/GP from 
source for AMD CPUs?


Regards,

Hermann.