[mythtv-users] SMP Performance

[Steven Adeff]

On 12/11/06, raphael <rpooser at gmail.com> wrote:
> Greg Grotsky wrote:
> >
> >
> > I just wonder how a single Opteron compares to an Athlon64 of the same
> > frequency when running X, myth, transcode jobs, etc.  According to
> > MSI's website my motherboard can take either of the 939-pin breeds.
> > When I upgrade my processor, I'd like to get the one more suited to
> > the job I need.  Basically, I wish I knew which one would be better
> > for our application.  I have yet to hear someone point to one
> > processor as the one for a myth machine.
> >
> > -Greg
> >
> >
>
> It probably doesn't matter too much.  I think an Opteron 165 is almost
> exactly like the corresponding X2 except it has a lower clock, and much
> bigger cache, 2x1MB.  The cores are named differently, from Manchester
> to Denmark, but that probably accounts for the extra cache.
> My personal opinion was at first that I wasn't considering the opteron
> and only wanted a 3800+ X2.  However, the $150 price that the 3800's
> were supposed to have seems to have gone scarce for the 939 version.
> The opteron 165 looks like a good replacement in that case, especially
> if you're willing to overclock it the extra 200MHz to get it up to the
> level of a 3800+... oops, more overclocking discussion.
>
> In all honesty I have no clue how myth depends on cache size.  Seems
> like if you answer that question you'll be able to tell which route to
> take, cache or mega-hurts.
> (for those that don't read the inq I know it's spelled Hertz).
> Raphael

Word on the street is that the Opteron's have a longer life when run
24x7 (even when overclocked). The larger cache also helps with video
encoding, though should have no real effect on decoding.
[Side Note: What I wonder though, is if running a PowerNow program
effects overclocking? In windows its easy to get info on the operating
speeds of your overclocked processor, but in linux, things like
CPUFreq seem to stick with the "known" speeds a CPU should be. For
instance, on my frontend, I have a KN1 Extreme with my Winchester
core. I've got it setup in the BIOS to run overclocked, but
cpufreq-info still shows it only as possibly being 1.0, 1.8 or 2.0GHz.
If anyone knows anymore on overclocking in linux, please email me off
list (or start a different thread), as I'd really like to get a better
idea if my BIOS settings are taking hold in linux, and if not, how to
get that to work properly.]