Re^2: Null-stripping performance


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Re^2: Null-stripping performance

by qiau (Initiate)

on Feb 26, 2007 at 13:52 UTC ( [id://602122]=note: print w/replies, xml )

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in reply to Re: Null-stripping performance
in thread Null-stripping performance

Oh, forgot to say that the strings are pretty large so I don't think arrays would be the best solution.

Each string is about 1 Mbyte that I read in from a file upon request so a standard use is to open about four files (sometimes more, sometimes less) and read values from different indexes in those strings.

I think I tried with a array in the beginning but realized that splitting into 1 Mbyte arrays wasn't fast at all :).

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Re^3: Null-stripping performance
by BrowserUk (Patriarch) on Feb 26, 2007 at 15:45 UTC

You did only do the unpack to an array once--not every time you needed a number--didn't you?

If that is the case, I'd benchmark combining substr and unpack against the other options:

my $str = ...;

sub fetchOne{ unpack 'a4', substr $str, $_[ 0 ] * 4, 4 }
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