O.K., I decided to check the same video (
http://www.youtube.com/watch?v=jdOevbchxOc) on both Mac OS 10.6.1 and Windows 7, and in Safari and another browser.
Here are the results for CPU usage:
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Windows System (my HTPC, it's AOPEN 45-DR)
Windows 7, 32bit, on an Intel C2D P9500 2.53 GHz, 4GB RAM (3GB used under W7-32bit), Intel onboard GMA X4500MHD graphics with Intel Beta W7 driver.
Safari: SD=10%-15%
HD=15%-20% (occasional spike to 25%)
IE8: SD=1%
HD=1%-3% (occasional spike to 5%)
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Mac System
OS 10.6.1, 24" iMac, 2.4 GHz. 2GB RAM, ATI Radeon HD2600
Safari 64bit: SD=43%-46% (234MB Real Mem)
HD=67%-77% (209.8MB Real Mem)
The SD value is the combination of Safari itself (HD=8%-9% (205MB Real Mem)), and the Flash Player (Safari Internet plug-in, which Safari calls for HD content, and which registers additional 35%-37% CPU and 29MB Real Mem).
The HD value is the combination of Safari itself (HD=13%-15% (175.1MB Real Mem)), and the Flash Player (Safari Internet plug-in, which Safari calls for HD content, and which registers additional 54%-62% CPU and 34.7MB Real Mem).
Camino 2.0b3: SD=34%-35% (102.6MB Real Mem)
HD=47%-49% (101.2MB Real Mem)
Firefox 3.5.4: SD=30%-33% (91.6MB Real Mem)
HD=43%-44% (99MB Real Mem)
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The way I look at this, performance-wise and resource-wise, Safari basically sucks, compared to both the Mozilla browsers, and IE8. I really do not see, how anyone half-way reasonable, can keep blaming Adobe for this kind of abysmal performance in Safari.
Also, when I open my iGoogle home page, Safari takes noticeably longer to load everything, than either Camino or Firefox. On Windows 7, Safari is noticeably faster to load the same page, than on the Mac.