Kamal from Kokata writes: For my non-professional home computer, which processor will be convenient: Double Core or Single Core ?
Hi, Kamal. Thanks for the great question.
I think that the question these days isn’t really “single core or dual core”, but “dual core or quad core.” I recently upgraded my cell phone from a single core Samsung Captivate to a dual-core Sony Xperia Ion, and let me tell you… the speed difference on Angry Birds is amazing.
So this question… like so many where computers are concerned… is “What will you be using your computer for?” If you basically use your e-mail for banking, chat, homework, maybe the occasional YouTube video, then a single-core processor is fine. And you can get them at bargain-basement prices (if you can find them) because retailers are trying to get rid of them. If you’re a casual gamer, like to stream HD Netflix movies, then you’ll probably want to go with a dual-core processor. If you’re a hardcore gamer or you edit HD movies and don’t want to wait a week for them to render, or you run architectural software or something like that, you might think about breaking down and getting a quad-core processor.
Here’s a way to think of the difference in speeds. Have you ever been at the bank or the theater with a long line and only one cashier or teller open? Things drag merrily along at a snail’s pace as you creep toward your destination. Then suddenly, miraculously, they open a second window. How much does that speed the line up? Then, they open a third and fourth window, which allows them to break the existing line in two, and process two people at a time from each of the lines. NOW how fast does the line move?
AMD tried introducing a tri-core processor for a while, but benchmark testing proved it to be not appreciably faster than the dual-core. The reason? It was still feeding from one line of data. With an odd number of cores, you lose the ability to sub-divide the line of data.
I hope that this helps.
Randal Schaffer
Tags: dual core, processing, quad core, single core, speed
I agree with your characterization of the workloads that benefit from more cores.
The comparison to a bank line is a little misleading. Tests have shown that adding a second core, or moving from 2 to 4 cores does not automatically double performance speed, or cut response time in half (depending on how you want to look at it). There are other limits on performance. The simplest one is that you have to be running 2 or 4 separate tasks to take advantage of the cores. Very little software is written to take full advantage of multiple cores. It it much harder to write a single program to do multiple things at once and get all of the timing right. And even if you can split it up, there will be points where it can only work on one cpu at a time because multiple threads are being consolidated or generated.
There is also the issue of shared resources. The whole computer has to be REdesigned to share RAM and Disk and Video access.
The bottom line is that performance improvement is not a 1:1 match to the increased number of cores. It is substantially less than that.