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CPU Influence on Load Times - Printable Version

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CPU Influence on Load Times - Don - 03-08-2012 01:01 AM

I am interested in learning more about what impact CPU power has on download times.

My question relates to whether upgrading my PC would have a noticeable effect on page download time. I see the "CPU Utilization" graph, but I'm not sure how to interpret that in regards to my question. And perhaps there are other test result details that would also be helpful in answering this question.

Thanks for any ideas.


RE: CPU Influence on Load Times - SWortham - 03-08-2012 02:11 AM

One issue is that the Javascript in the <head> of a page has to download and be interpreted (or compiled) and execute before the page starts rendering. This will affect load times. And a faster CPU should help with this somewhat.

Quote:Traditionally, a <script> node blocks (or "hangs") the browser while it is being processed, preventing the rest of the page from loading. Because document.write() or other javascript in the block may inject HTML into the document structure at parse time, browsers generally have to stop rendering in order to parse and evaluate the javascript block before continuing. This is undesirable.

There's also CSS layout and HTML rendering. If you've got a huge amount of HTML on your page with complicated CSS rules then the CPU might be working pretty hard for half a second or so before rendering. Most sites aren't that bad about this though.