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

[Dennis Luehring]

Am 18.08.2015 um 10:19 schrieb Aurelien Jarno:
> How big is the source file and the output file? I find strange that I/O
> impacts so much for a compilation which should be CPU bounded. Maybe try
> to add the -pipe argument to g++.

NetBSD SPARC64, running from ramdisk, qemu 2.4.50

g++ src/pugixml.cpp -g -Wall -Wextra -Werror -pedantic -std=c++0x -c 
-MMD -MP
#1: 2:52.6
#2: 2:49.2
g++ src/pugixml.cpp -g -Wall -Wextra -Werror -pedantic -std=c++0x -c 
-MMD -MP -pipe
#3: 2:50.2
#4: 2:52.1

pugixml.cpp:  323.273 bytes
pugixml.o:  1.095.832 bytes
pugixml.d:        101 bytes

Stop after the preprocessing stage:
g++ src/pugixml.cpp -g -Wall -Wextra -Werror -pedantic -std=c++0x -c 
-MMD -MP -E > pugixml.prep.cpp

runtime: ~5sek

pugixml.cpp.prep: 788.350 bytes

Stop after the stage of compilation proper:
g++ src/pugixml.cpp -g -Wall -Wextra -Werror -pedantic -std=c++0x -c 
-MMD -MP -S
runtime #1: 2:40.1
runtime #2: 2:41.0

Compile or assemble the source files, but do not link:
g++ src/pugixml.cpp -g -Wall -Wextra -Werror -pedantic -std=c++0x -c 
-MMD -MP -c
runtime: 2:52.6