[laptop-mode] Silent web browsing

[Luis Garrido]

Hi!

I thought I'd share some of my experiences about trying to avoid
spin-ups when browsing the internet.

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Firefox 3
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Apparently FF3 uses sqlite as backend for history, bookmarks, etc.
Sqlite fsyncs a lot to keep the database consistent, so you get an
fsync (with the consequent spin-up) every new page you open. Here is
more info on the subject:

http://shaver.off.net/diary/2008/05/25/fsyncers-and-curveballs/

However, FF3 doesn't provoke spin-ups if you are just reading a long
page, without clicking any links or opening new stuff.

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Opera 9
-------------------

Opera 9 exhibits the opposite behaviour: clicking and opening new
stuff won't spin-up your HD, but you'll get some random spin-ups every
now an then, even if you are not navigating. Perhaps it somehow
consolidates writes and issues the occasional fsync, I haven't
investigated it.

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Conclusion
-------------------

Apparently the only reliable way of achieving silent browsing is
moving your browser user profile to a ramdisk (tmpfs). If you want to
store your session history and the bookmarks you create during it you
will have to implement some way of mirroring it to the hard disk via a
cron rsync job, for instance.

Cheers,

Luis