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Hardware/system clock speed.

Posted: 21. Dec 2011, 11:48
by john.doe
Hi, to be honest I've never used VirtuaBox, but I'd like to know if this is possible to achieve.
I'd like to slow down (virtual) hardware or system clock speed by 10 or more times. So for example - 1 second in virtualboxed system is like 20 normal (real) seconds. Some scripts on websites use hardware clock to measure time so slowing down only the browser (with cheatengine or speedgear etc.) wont' help.

I'm looking for any software which will allow me to achieve that.

Thanks.

Re: Hardware/system clock speed.

Posted: 21. Dec 2011, 13:25
by mpack
Nope. VirtualBox is a hypervisor, not a simulator - so code runs natively on the host CPU, at whatever clock rate the host CPU uses.

Re: Hardware/system clock speed.

Posted: 21. Dec 2011, 16:15
by privattomtom
john.doe wrote:Hi, to be honest I've never used VirtuaBox, but I'd like to know if this is possible to achieve.
I'd like to slow down (virtual) hardware or system clock speed by 10 or more times. So for example - 1 second in virtualboxed system is like 20 normal (real) seconds. Some scripts on websites use hardware clock to measure time so slowing down only the browser (with cheatengine or speedgear etc.) wont' help.

I'm looking for any software which will allow me to achieve that.

Thanks.
VBoxManage controlvm -cpuexecutioncap
The cpuexecutioncap <1-100>: This operation controls how much cpu time a virtual CPU can use. A value of 50 implies a single virtual CPU can use up to 50% of a single host CPU.

VirtualBox Manual page 124

Re: Hardware/system clock speed.

Posted: 21. Dec 2011, 17:29
by mpack
privattomtom wrote:VBoxManage controlvm -cpuexecutioncap
Um... that doesn't change the clock speed. When the guest is given its time slice it will run at the full clock speed. The execution cap simply prevents a VM from hogging the CPU to the exclusion of other tasks (particularly host tasks). Timers should be unaffected.

Re: Hardware/system clock speed.

Posted: 21. Dec 2011, 17:37
by john.doe
I see. Many of you here have some serious computer knowlegde, so i'd like to ask if you know any other way to achieve that?

Basically what I need is to reconfigure software clock (the one that OS uses, not the CMOS). I found out that it has some layers (OS itself use low layer software clock, and higher layer is for applications). But i couln't find any way how to get into that.

It also may be accessable in virtualized system (VMware?).

I will appreciate any help.

Re: Hardware/system clock speed.

Posted: 21. Dec 2011, 19:36
by Perryg
Perhaps if you explained what this is for we could come up with an approach that will work.