[Autogenerated] let's see some details about the Quantum.
So the first thing we can do is run the clock reds tool from
Sysinternals it's a command line tool you can just run it.
So here is the first time running that on that machine and you can see the
maximum timer interval indicating here as 15.625 millisecond.
That's the number we've seen the previous slide and that's the
default number used for the basis of the Quantum.
So the Quantum on client machines is twice this number and the Quantum on
several machines by default is 12 times this number.
You can also see there is a minimum time interval
here in current timer interval.
So in fact the current is actually much smaller around one
millisecond and this happens because some process at least one
requested the timer to run at a higher resolution,
the higher rate, but this doesn't really change the quantum length.
It just so happens that the schedule now wakes up in shorter interval.
In fact it wakes up everyone millisecond.
It has two.
However, still in terms of measurement of quantum,
it's still going to use the base number as the basis of measuring the
interval for for the timer for the quantum of threads.
Now,
why do we have these shorter intervals that are being
programmed here for the internal timer?
This is typically because of applications using multimedia such as audio
and video and they require much more precise timing.
The default is provided.
Obviously this makes the system burn more power but this is
typically what you'll find on a typical system.
The minimum time interval is really is something that
depends on the hardware platform,
the capabilities of the hardware and half a millisecond
is fairly common in today's hardware.
So that's one thing.
How can we tell the difference between the client or the server?
In fact, can we perhaps switch that that quantum length?
Now one way of doing that is by tweaking the registry.
Like I said,
I will not show that but I will show something that Windows
does provide in a dialogue that I like to call the most
misunderstood dialog in Windows.
So if you search for about your PC which will launch the settings window here,
you can see there's some stuff here.
But what I want to get to is something called advanced system settings and
this still launches the old or the classic dialogue here and you can see
under performance there's another settings and then there's another tab
called advanced that's really advanced.
And this tab of this dialog is something I like to call the
most misunderstood dialogue and Windows.
Let me show you why now it actually has two pieces.
The lower piece says virtual memory and in information here is about
the size of all the page files that have been configured for this
machine and that's in fact fairly understood.
The upper part here is the misunderstood part.
It says processor scheduling,
choose how to allocate processor resources and just for best
performance of programs or background services?
Well actually I like both of them to run.
Just great.
Why do I have to choose what's programs anyway,
what's background services anyway?
What does that all these dollar really mean?
So this is really about the Quantum and the behavior related
to that Quantum such as the quantum stretching that only uh
quantum boosting if you will, that only happens on client machines.
So programs just says I would like to have short Quantum's uh
roughly 30 million seconds in length and I want to have quantum
boosting and other priority boots related to uI activity because
this is supposed to be a client machine.
If I change here to background services and click apply
this in fact applies immediately.
Long Quantum's exactly as you find when you look at a server machine,
this is where that radio button would be.
This implies long Quantum's roughly 180 milliseconds and there is
no quantum stretching and there is no boost,
no boost that's going to be provided because of your activity because
the assumption is that this is a server machine and no interactive
users usually working with the system.
So some people for example that work with the server machine as their
client machine because they have some kind of need to work with certain
tools that are only present on on server machines.
They should probably go back and change that to
programs so they get more comfortable.
behavior would say that it's more appropriate for an interactive
machine where a human user is working with the system.
So shorter Quantum's are typically better and getting all these
boost for quantum stretching and some priority boost rated to
UI activity is also beneficial.
So this is this dialogue that I like to call the most
misunderstood dialog in Windows.
If you know of a less understood dialogue, please hit me up in the comments.