Re^7: Working with fixed length files (Crap benchmark!)

[BrowserUk]

The reason all the code runs the same speed is because sysread doesn't work on ramfiles, so the loops are never being entered.

That also explains the dramatic slowdown affect of local $/ = \nnn;. It adds an operation to a call that does almost nothing, and twice almost nothing is longer than 1 times almost nothing.

Which brings up another mystery entitled: "The Strange Case of the Disappearing AutoDie".

[Tux]

autodie was removed so I could bench on older perls.

Good analisys! That should teach me :/

sysread basically means "bypass PerlIO, do a read ()", so that means PerlIO::scalar doesn't get a say in it. However whether that is how things should be is a different matter.

[Tux]

With all sysread's re-placed by read's my bench shows much more reliable figures:

       Rate  buk ike1 ike2
buk  81.1/s   -- -43% -46%
ike1  143/s  76%   --  -5%
ike2  150/s  85%   5%   --

I think it would be hard to reduce the overhead even more.

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