[wine-devel] Re: Severe regression in wine startup latencies

[Alan W. Irwin]

On 2011-08-29 07:56+1000 Ben Peddell wrote:

> On 29/08/2011 2:37 AM, Alan W. Irwin wrote:
>> bash.exe-3.1$ time /z/home/wine/newstart1/MinGW/msys/1.0/bin/echo.exe
>> hello
>> hello
>>
>> real    0m0.503s
>> user    0m0.080s
>> sys     0m0.020s
>>
>> Also, I tried
>> time (x; x; x; x; x; x; x; x; x; x), where "x" represents the complete
>> echo command above, and the result was
>>
>> real    0m5.281s
>> user    0m0.800s
>> sys     0m0.200s
> [snip]
>>
>> While I am doing those additional investigations, please consider the
>> question of why there is a huge difference between built-in and
>> executable latency for MSYS bash commands under wine.  To start that
>> investigation it would be good to compare the wine results for those
>> two cases with the Windows results for those two cases.  (I assume the
>> two time results for built-in versus executable will be fairly similar
>> in the Windows case, but that assumption needs to be checked.) I don't
>> have access to Windows myself. Anybody up for doing that simple test
>> and reporting the results back here?  The automatic MinGW/MSYS
>> installer at http://sourceforge.net/projects/mingw/files/Automated
>> MinGW Installer/mingw-get-inst/ makes it easy to install the relevant
>> MinGW/MSYS software on both wine and Windows.
>
> Under MSYS 1.0.17 running on Windows 7 x64 SP1:
>
> bash.exe-3.1$ /bin/bash --version
> GNU bash, version 3.1.17(1)-release (i686-pc-msys)
> Copyright (C) 2005 Free Software Foundation, Inc.
>
> bash.exe-3.1$ alias x='/bin/echo.exe -n .'
>
> bash.exe-3.1$ time x
> .
> real    0m0.031s
> user    0m0.000s
> sys     0m0.015s
>
> bash.exe-3.1$ time (x;x;x;x;x;x;x;x;x;x)
> ..........
> real    0m0.296s
> user    0m0.075s
> sys     0m0.136s
>
> This shows a latency of approximately 2 jiffies for each command - 1
> jiffy in Windows is 15.6ms.
>
> -- 
> Ben Peddell
> IT Support Bowen, Collinsville, Proserpine and Home Hill Catholic schools
> http://klightspeed.killerwolves.net/

Thanks, Ben, for doing the requested test for the executable echo
test. That shows the Windows startup latency is measureable but
acceptable for that executable.  Just out of curiosity, what happens
for the corresponding bash executable built-in echo functionality?  Is
it essentially instantaneous (i.e., elapsed time less than 0.001
seconds) like in the wine case?

Alan
__________________________
Alan W. Irwin

Astronomical research affiliation with Department of Physics and Astronomy,
University of Victoria (astrowww.phys.uvic.ca).

Programming affiliations with the FreeEOS equation-of-state
implementation for stellar interiors (freeeos.sf.net); the Time
Ephemerides project (timeephem.sf.net); PLplot scientific plotting
software package (plplot.sf.net); the libLASi project
(unifont.org/lasi); the Loads of Linux Links project (loll.sf.net);
and the Linux Brochure Project (lbproject.sf.net).
__________________________

Linux-powered Science
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