Re: Advice on system purchase
Am Montag, 29. Oktober 2012 schrieb Martin Steigerwald:
> Am Sonntag, 28. Oktober 2012 schrieb Marc Shapiro:
> > On 10/27/2012 08:27 PM, Stan Hoeppner wrote:
> > > On 10/27/2012 7:29 PM, Marc Shapiro wrote:
> > >> I'm really getting annoyed by my random system lockups, so I have
> > >> been looking at new motherboards, new systems, etc.
> > >
> > >
> > >
> > > ...
> > >
> > >
> > >
> > >> I saw a Fry's add for a motherboard, an AMD 8 Core CPU and memory
> > >> for
> > >
> > >
> > >
> > > That's a 125 watt CPU (ouch!). That's two 60 watt incandescent
> > > bulbs worth of juice and heat output at full load, one bulb worth
> > > at idle, and a relatively loud stock cooler to prevent it from
> > > melting.
> > >
> > >
> > >
> > > Coming from a 2800+ which is a ~60 watt CPU, and given the fact
> > > you'll never make use of more than 2 of those 8 cores, I recommend
> > > a dual core AthlonII X2 @ 3.4GHz. I have the 3GHz model and the
> > > 2nd core is pretty much always idle, with primary core being idle
> > > most of the time as well, as is everyone's.
> >
> >
> >
> > I don't know if this makes a difference, but... While this is a home
> > machine there are three of us here. Myself, my wife and daughter. We
> > are all logged in all the time and we are all running separate X
> > sessions all the time. That way, it is just a Ctl-Alt-Fx keystroke
> > for any one of us to get to our session as we left it. Will
> > multiple X sessions each run in their own core, or will they all be
> > running in a single core. If the former, then I can make use of
> > some of those extra cores, if the latter, then fewer cores running
> > at faster speeds does make more sense. Can anyone answer this
> > question?
>
> You should have one X server process for each display.
>
> And that answers the question, cause Linux is perfectly capable to
> distribute different processes as well as different threads over
> different cores.
And a ton of other processes for each session.
So yes, Linux will scale this to mutiple cores.
But I doubt whether 8 cores are needed as long as only one person works
simultaneously on the machine. I think 8 cores are more than Linux can
fully utilize in that workload.
See:
PowerTOP v2.0 Overview *Idle stats* Frequency stats Device stats Tunables
Package | Core | CPU 0 CPU 1
| | C0 active 7,3% 3,2%
| | POLL 0,0% 0,0 ms 0,0% 0,0 ms
| | C1-SNB 5,2% 0,5 ms 3,2% 1,1 ms
C2 (pc2) 0,0% | |
C3 (pc3) 0,0% | C3 (cc3) 5,7% | C3-SNB 4,5% 0,8 ms 1,9% 2,8 ms
C6 (pc6) 0,0% | C6 (cc6) 0,2% | C6-SNB 0,2% 0,7 ms 0,0% 0,2 ms
C7 (pc7) 0,0% | C7 (cc7) 74,9% | C7-SNB 82,9% 1,2 ms 91,7% 3,7 ms
| Core | CPU 2 CPU 3
| | C0 active 4,9% 3,2%
| | POLL 0,0% 0,0 ms 0,0% 0,0 ms
| | C1-SNB 1,1% 0,3 ms 0,6% 0,3 ms
| |
| C3 (cc3) 1,5% | C3-SNB 1,5% 0,8 ms 0,6% 0,4 ms
| C6 (cc6) 1,1% | C6-SNB 1,1% 2,3 ms 0,0% 0,0 ms
| C7 (cc7) 85,9% | C7-SNB 91,4% 2,9 ms 95,7% 2,2 ms
PowerTOP v2.0 Overview Idle stats *Frequency stats* Device stats Tunables
Package | Core | CPU 0 CPU 1
| | Actual 2,6 GHz 2,6 GHz
Turbo Mode 9,9% | Turbo Mode 0,5% | Turbo Mode 0,2% 0,4%
2,50 GHz 0,0% | 2,50 GHz 0,0% | 2,50 GHz 0,0% 0,0%
2,00 GHz 0,1% | 2,00 GHz 0,0% | 2,00 GHz 0,0% 0,0%
1,80 GHz 0,1% | 1,80 GHz 0,0% | 1,80 GHz 0,0% 0,0%
1,60 GHz 0,1% | 1,60 GHz 0,0% | 1,60 GHz 0,0% 0,0%
1400 MHz 0,0% | 1400 MHz 0,0% | 1400 MHz 0,0% 0,0%
1200 MHz 0,6% | 1200 MHz 0,0% | 1200 MHz 0,0% 0,0%
1000 MHz 0,2% | 1000 MHz 0,0% | 1000 MHz 0,0% 0,0%
800 MHz 52,2% | 800 MHz 1,3% | 800 MHz 0,7% 0,7%
Idle 36,8% | Idle 98,1% | Idle 99,1% 98,8%
| Core | CPU 2 CPU 3
| | Actual 2,6 GHz 2,6 GHz
| Turbo Mode 9,7% | Turbo Mode 9,7% 3,5%
| 2,50 GHz 0,0% | 2,50 GHz 0,0% 0,0%
| 2,00 GHz 0,1% | 2,00 GHz 0,1% 0,0%
| 1,80 GHz 0,1% | 1,80 GHz 0,1% 0,0%
| 1,60 GHz 0,1% | 1,60 GHz 0,1% 0,0%
| 1400 MHz 0,0% | 1400 MHz 0,0% 0,0%
| 1200 MHz 0,5% | 1200 MHz 0,5% 0,1%
| 1000 MHz 0,2% | 1000 MHz 0,2% 0,0%
| 800 MHz 51,5% | 800 MHz 51,3% 4,9%
| Idle 37,7% | Idle 37,9% 91,4%
Idling. Most of the time just idling. Except for one hyperthreading unit
on one of the two cores. (There is a slight time difference between
the two snapshots that are likely to explain the different idle values).
So it comes down to what peak performance do you need? What is the most
demanding task you or some member of your family wants to run on that
machine?
I bet even for three people with light desktop work and possibly some
youtube videos or so a dual or quad core would have more than enough
power.
Ciao,
--
Martin 'Helios' Steigerwald - http://www.Lichtvoll.de
GPG: 03B0 0D6C 0040 0710 4AFA B82F 991B EAAC A599 84C7
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