Re: How to measure boot time in bochs?

Hello, 

1. There are differences in the supported instructions. Some processors supports SSE4 instructions subset, some don't, for example. You can look at Bochs source code for details. 

2. Bochs is open source. You can always experiment. Just be aware that if you modify an existing instruction, current IA32/AMD64 OS and/or software may stop working as expected on your own build. 

Regards, 

Xavier 

----- Mail original -----

> De: "朱朱乐乐" <[email protected]>
> À: "Stanislav" <[email protected]>
> Cc: [email protected]
> Envoyé: Samedi 15 Juin 2013 04:07:51
> Objet: Re: [Bochs-developers] How to measure boot time in bochs?

> 1. MY FIRST QUESTION

> Since Bochs has provided different models like intel i7 or amd, I am
> wondering what's the difference since they are all executing the
> same assembly instructions.

> As far as I see the only difference is the difference of ips.

> 2. MY SECOND QUESTION

> Is it possible if I want to add an assembly instruction or alternate
> the function of an assembly instruction?

> 2013/5/10 朱朱乐乐 < [email protected] >

> > Thank you!
> 
> > I tried your method and it works!
> 

> > 2013/5/4 Stanislav < [email protected] >
> 

> > > How about using your creativity to answer the trivial question ?
> > 
> 

> > > 1. You could always chose arbitrary number and see what is does.
> > > Is
> > > benchmark is long enough to be representative? Does the
> > > simulation
> > > reach the goal (like desktop screen rendered) ?
> > 
> 

> > > 2. You could repeat (1) multiple times with different N and find
> > > the
> > > best one
> > 
> 

> > > 3. You could read Bochs log file and find exact N
> > 
> 

> > > And all this is before I even started to think about it.
> > 
> 

> > > Stanislav
> > 
> 

> > > From: 朱朱乐乐 [mailto: [email protected] ]
> > 
> 
> > > Sent: Saturday, May 04, 2013 5:21 AM
> > 
> 
> > > To: Stanislav
> > 
> 
> > > Cc: [email protected]
> > 
> 
> > > Subject: Re: [Bochs-developers] How to measure boot time in
> > > bochs?
> > 
> 

> > > I tried using Bochs –f .bochsrc.winxp –benchmark 4000 .
> > 
> 

> > > But I don't know how to figure out the number 4000.
> > 
> 

> > > 2013/4/30 Stanislav < [email protected] >
> > 
> 

> > > I will explain how do I measure it.
> > 
> 

> > > First of all you could always measure the host wall clock but now
> > > comes a question how can you make sure you measure equal work.
> > 
> 

> > > I use fixed disk image (volatile format to make sure it doesn’t
> > > change between experiments) and fixed .bochsrc configuration
> > > file.
> > 
> 
> > > Then I use –benchmark N option of Bochs.
> > 
> 
> > > With this option Bochs runs exactly N million emulated cycles and
> > > closes itself so you could measure equal work always.
> > 
> 
> > > For example to boot WinXP it is enough to run 4B = 4000M emulated
> > > ticks (or instructions because in Bochs every instruction count a
> > > tick except when CPU is halted).
> > 
> 
> > > So for WinXP boot time measurement I was using:
> > 
> 

> > > Bochs –f .bochsrc.winxp –benchmark 4000
> > 
> 

> > > Stanislav
> > 
> 

> > > From: 朱朱 乐乐 [mailto: [email protected] ]
> > 
> 
> > > Sent: Monday, April 29, 2013 3:51 PM
> > 
> 
> > > To: [email protected]
> > 
> 
> > > Subject: [Bochs-developers] How to measure boot time in bochs?
> > 
> 

> > > I am tring to conduct a performance optimizing experiment and I
> > > want
> > > to measure the boot time of Linux distro such as Fedora 18.
> > 
> 

> ------------------------------------------------------------------------------
> This SF.net email is sponsored by Windows:

> Build for Windows Store.

> http://p.sf.net/sfu/windows-dev2dev
> _______________________________________________
> bochs-developers mailing list
> [email protected]
> https://lists.sourceforge.net/lists/listinfo/bochs-developers

------------------------------------------------------------------------------
This SF.net email is sponsored by Windows:

Build for Windows Store.

http://p.sf.net/sfu/windows-dev2dev

_______________________________________________
bochs-developers mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/bochs-developers