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

[Dennis Luehring]

currently qemu emulates an TI UltraSparc IIi (Sabre)
does that mean that qemu emulates the sparc somwhere around 270-480Mhz 
(i can't find the running mhz in qemu)

how can i get the Mhz the sparc is running?
(cpuinfo and lscpu missing Mhz, dmidecode is not available, 
/sys/devices/system/cpu/cpu*/cpufreq/scaling_max_freq is empty, lshw 
does not show anything)

is there a way to increase the clock speed of the cpu/fpu without 
killing other timemings - or switch to a different cpu?
(because i do not need real speed behavior for my testing)

another benchmark

sysbench (0.4.12) --num-threads=1 --test=cpu --cpu-max-prime=2000 run
  Host x64    :   1.3580s
  Qemu SPARC64: 184.2532s

------------------------------
/proc/cpuinfo:

cpu             : TI UltraSparc IIi (Sabre)
fpu             : UltraSparc IIi integrated FPU
pmu             : ultra12
prom            : OBP 3.10.24 1999/01/01 01:01
type            : sun4u
ncpus probed    : 1
ncpus active    : 1
D$ parity tl1   : 0
I$ parity tl1   : 0
Cpu0ClkTck      : 0000000005f5e100
cpucaps         : flush,stbar,swap,muldiv,v9,mul32,div32,v8plus,vis
MMU Type        : Spitfire

lscpu:

Architecture:          sparc64
CPU op-mode(s):        32-bit, 64-bit
Byte Order:            Big Endian
CPU(s):                1
On-line CPU(s) list:   0
Thread(s) per core:    1
Core(s) per socket:    1
Socket(s):             1

https://en.wikipedia.org/wiki/UltraSPARC_II

UltraSPARC IIi

The UltraSPARC IIi "Sabre" was a low-cost version introduced in 1997 
that operated at 270 to 360 MHz.
It was fabricated in a 0.35 µm process and possessed a die size of 156 mm².
It dissipated 21 W and used a 1.9 V power supply. It had a 256 KB to 2 
MB L2 cache.
In 1998, a version code-named Sapphire-Red, was fabricated in a 0.25 µm 
process, enabling
the microprocessor to operate at 333 to 480 MHz. It dissipated 21 W at 
440 MHz and used a 1.9 V power supply.

---------------------------------
my host machine is

lscpu

Architecture:          x86_64
CPU op-mode(s):        32-bit, 64-bit
Byte Order:            Little Endian
CPU(s):                8
On-line CPU(s) list:   0-7
Thread(s) per core:    2
Core(s) per socket:    4
Socket(s):             1
NUMA node(s):          1
Vendor ID:             GenuineIntel
CPU family:            6
Model:                 30
Model name:            Intel(R) Core(TM) i7 CPU       Q 740  @ 1.73GHz
Stepping:              5
CPU MHz:               933.000
CPU max MHz:           1734,0000
CPU min MHz:           933,0000
BogoMIPS:              3458.22
Virtualization:        VT-x
L1d cache:             32K
L1i cache:             32K
L2 cache:              256K
L3 cache:              6144K
NUMA node0 CPU(s):     0-7


Am 28.07.2015 um 11:54 schrieb Artyom Tarasenko:
> On Tue, Jul 28, 2015 at 9:52 AM, Dennis Luehring <address@hidden> wrote:
> > (i've posted the question already on address@hidden but was toled
> > to better use this mailing list)
> >
> > i've prepared an Debian 7.8.0 image for SPARC64/qemu emulation for C/C++
> > development before-real-hardware big-endian/unaligned tests
> >
> > i've benchmarked compiling of single pugixml.cpp
> > (https://github.com/zeux/pugixml/blob/master/src/pugixml.cpp)
> >
> > qemu-system-sparc64: >180sek
> > x64 native : ~ 2sek
> >
> > so my sparc64 emulation is around 90 times slower then native x64
> >
> > my system:
> >
> > using lastest qemu git 2.3.x, with virtio for harddisk/network and qcow2
> > image
> >
> > https://depositfiles.com/files/sj20aqwp0 (~280MB
> > press the "regular download" button, wait some seconds, solve the
> > chapca, "download file in regular mode by browser"
> >
> > there is pugi_sparc.txt in the 7z which describes how to start,use and
> > what is installed in the image
> >
> > qemu runs natively under a ubuntu 15.04 (x64), Core i7, 8GB system doing
> > nothing but qemu
> >
> > installed is
> >
> > gcc/g++ 4.6
> > make
> > sshd running
> >
> > compiling cmake 2.3.2 tooked around 10h
> > compiling pugixml takes also very very long
> >
> > "top perf" from guest and host while compiling pugixml don't show big
> > blockers or something over time
> > http://pastebin.com/D2fUpPrM
> >
> > anything i can do to speedup the emulation?
>
> Maybe try the fresh tcg optimizer improvements from Aurelien:
> https://lists.gnu.org/archive/html/qemu-devel/2015-07/msg05133.html
>
> Artyom