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Comment by rarestblog | Hacker News Reader

Please increase delta range down to 1ms, Chrome barely uses CPU power at 10ms. 6 tabs @10ms uses 25% of Core2Duo.

Also decrease rate at which HTML stats are updated - DOM update slows stuff down, it should update stats only once a second or so.

Updated to 1ms! I'll work on the HTML stat updates

Edit: fixed and fixed

Now we're talking! 7 tabs = 80% cpu usage!

You might also consider lookup tables for Hamming distance (google for "counting bits").

Yeah, my JS hamming distance implementation is pretty miserable. I'm no bit wizard, but I thikn I can modify the SHA1 function (before it returns the value as a hex string) and XOR the 5 vars with the hex value that they gave us, and then count the set bits. Couldn't get it working last night though so I switched over to this

You might also consider removing UTF8Encoding from SHA1 implementation, I might be wrong, but I think contest states no encoding should be used - i.e. ASCII only. If that's a care, that's a useless O(N) operation.

UTF8(ASCII) == ASCII

Unless you're using characters > 255, UTF-8 is identical to ASCII.

Actually it's UTF8(ASCII) == ASCII iff ASCII < 128, since the MSB signifies a multi-byte character.

http://en.wikipedia.org/wiki/UTF-8

Hm, on second thought UTF8(ASCII) is -always- == ASCII, since ASCII is only defined for 0-127, unless you count the extended variants :P

http://en.wikipedia.org/wiki/ASCII

Hah! I just generated as many hashes in a minute that I did in the hour I had it running beforehand. Good changes :)

You could also make use of the fancy new worker thread stuff in browsers that support it. Should let you skip the timeout altogether.

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