Re: [Qemu-devel] Debian 7.8.0 SPARC64 on qemu - anything i can do to speedup the emulation?

[Dennis Luehring]

Am 31.07.2015 um 17:43 schrieb Aurelien Jarno:
> > >Anyway I have extracted this code into a C file (see attached file) that
> > >can more easily compiled to 32 or 64 bit using -m32 or -m64. I observe
> > >the same behavior than sysbench, even with qemu-user (which is not
> > >surprising as the above code doesn't really put pressure the MMU.
> > >
> > >Running it in I get the following time:
> > >x86-64 host       0.877s
> > >sparc guest -m32  1m39s
> > >sparc guest -m64   3.5s
> > >opensparc T1 -m32 1m59s
> > >opensparc T1 -m64 1m12s

i've redone the benchmarks with Debian and NetBSD SPARC64

host: Ubuntu 15.04 x64 (latest updates) i7, 8 Cores, 8 GB RAM
  uname -a
  Linux dl-Precision-M6500 3.19.0-25-generic #26-Ubuntu SMP Fri Jul 24 
21:17:31 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux

  file /usr/bin/gcc
  /usr/bin/gcc: symbolic link to `gcc-4.9'
  file /usr/bin/gcc-4.9
  /usr/bin/gcc-4.9: ELF 64-bit LSB executable, x86-64, version 1 
(SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.32, 
BuildID[sha1]=f9897a3711d41df1d427f81bf3a60a60c377cd12, stripped

----------------

qemu: qemu 2.3.93 build from source

  file ~/qemu/sparc64-softmmu/qemu-system-sparc64
  /home/dl/qemu/sparc64-softmmu/qemu-system-sparc64: ELF 64-bit LSB 
shared object, x86-64, version 1 (SYSV), dynamically linked (uses shared 
libs), for GNU/Linux 2.6.32, 
BuildID[sha1]=8cae7ad397bb9beb12d1ad670c3170a8dceef139, not stripped

----------------

guest-debian: Debian 7.8.0 SPARC64 (mixed 32/64 bit kernel/userland)

uname -a
Linux debian 3.2.0-4-sparc64 #1 Debian 3.2.68-1+deb7u2 sparc64 GNU/Linux

32bit GCC

file /usr/bin/gcc
/usr/bin/gcc: symbolic link to `gcc-4.6'
file /usr/bin/gcc-4.6
/usr/bin/gcc-4.6: ELF 32-bit MSB executable, SPARC32PLUS, V8+ Required, 
version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 
2.6.26, BuildID[sha1]=0x64ad1bef0a0bfdb8780363e811c39b7c97d567ac, stripped

----------------

guest-netsbd: NetBSD 6.1.5 SPARC64
(according to the documentation + mailing list questions its pure 64bit 
kernel and userland)

uname -a
NetBSD myhost.mydom 6.1.5 NetBSD 6.1.5 (GENERIC) sparc64

64bit GCC

file /usr/bin/gcc
/usr/bin/gcc: ELF 64-bit MSB executable, SPARC V9, relaxed memory 
ordering, (SYSV), dynamically linked (uses shared libs), for NetBSD 
6.1.5, not stripped

----------------

benchmarks:

compilation pugixml 1.6 pugixml.cpp:
g++ src/pugixml.cpp -g -Wall -Wextra -Werror -pedantic -std=c++0x -c 
-MMD -MP

host: ~3 sec
guest-debian: ~3:52.6 (32bit gcc)
guest-netbsd: ~3:27.6 (64bit gcc)

runtime Aurelien Jarnos prime.c
gcc prime.c -o prime.out -lm

host: ~2 sec
guest-debian(-m32): ~3:37.5
guest-debian(-m64): ~11 sec
guest-netbsd(only -m64): ~11 sec

Aurelien Jarnos explained the "11 sec" boost running prime.c using -m64, 
but still the NetBSD 64bit gcc needs 3:27.6 to compile pugixml.cpp - its 
just
one file, 1GB of RAM, no swapping