OT : More CPUs or Faster CPUs

[Chris Snook]

Paul Lemmons wrote:
> I am soon to purchase a new PC. It will run Fedora and its primary 
> purpose will be:
> 
> 1) Transcoding my DVD library to xvid-avi's so that they may be watched 
> on my media player
> 2) Editing training videos that I create and burning the finished 
> product to DVD for distribution
> 
> To transcode I will most likely be using dvd::rip and for editing I will 
> probably be using cinerella
> 
> Now that that is said and money not a limitless resource I have some 
> choices to make. One of those choices is CPU configuration. For the 
> tasks above, which is better:
> 
> 1) A single very fast CPU

These don't exist anymore.  All the high-end commodity chips are at least dual-core.

> 2) Dual core CPU with combined speed greater than or equal to a single 
> CPU but each core slower than a single CPU

Actually, dual-core goes higher in both clock speed and cache-per-core these days.

> 3) Multi socket CPU with combined speed greater than a single CPU but 
> each CPU slower than a single CPU

This only makes sense if you have a multi-threaded application, and a lot of 
money.  You may also end up needing a RAID array to have enough I/O throughput 
to benefit from this.

> Bang for buck, option 2 sounds the best to me but I am concerned that 
> the process of transcodeing is single threaded and would not take 
> advantage of multiple CPUs.
> 
> Thoughts? Suggestions?

If your app is multithreaded, but you don't want to break the bank, consider a 
single quad-core CPU.  You won't get the memory bandwidth boost from going 
multi-socket, but transcoding should be mostly cache and CPU-bound anyway. 
Transcoding should scale very well to multiple CPUs, if you have a multithreaded 
implementation.

	-- Chris