john-users - OpenMP not using all threads

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Date: Sat, 19 Nov 2011 16:29:12 -0500
From: Stephen Reese <rsreese@...il.com>
To: john-users@...ts.openwall.com
Subject: OpenMP not using all threads

I have patched john-1.7.8.tar.gz with john-1.7.8-omp-des-7.diff.gz in
order to utilize four threads from a E5520 on a Debian system but it
instead seem like it is only using two. When testing DES I see around
2500K c/s and when patched about 5000K. I was hoping for closer to
8000K to 10000K.

Here is the cpuinfo:

flags : fpu de tsc msr pae cx8 cmov pat clflush mmx fxsr sse sse2 ss
ht nx constant_tsc nonstop_tsc pni ssse3 sse4_1 sse4_2 popcnt
hypervisor

To ensure gcc (Debian 4.4.5-8) is working as intended the following
was tested and 4 threads are returned.

https://en.wikipedia.org/wiki/OpenMP#C

I also edited the Makefile as follows:

# gcc with OpenMP
OMPFLAGS = -fopenmp -msse2

Another strangeness is when testing is I am not seeing the -16
appending to the following:

Benchmarking: Traditional DES [128/128 BS SSE2]... DONE

Is this normal or did something go wrong.