Re: [perl #122955] [PATCH] speed up building with less disk IO pod moves+__END__+misc

On Sun, Oct 12, 2014 at 7:53 PM, Father Chrysostomos via RT
<perlbug-followup@perl.org> wrote:

>> I'd considered reading perl source with a buffer size of 4096 to be a
>> bug in itself.
>
> Could you clarify?

Reading 4K at a time off disk is going to be inefficient compared to
reading larger chunks, especially if we're stopping to expand memory
and/or percolate up through the perlio layers each time.  When using
perlio, the perlio buffer should be the larger of 8192 and BUFSIZ,
which increased speed dramatically compare to 4K buffers.  See

http://perl5.git.perl.org/perl.git/commitdiff/b83080de5c42543809ce9004bcdbcd3162a00e70

Of course 8K is pretty small by today's standards so that could
probably be revisited.  One of the problems is that the buffer is the
same size regardless of whether we're reading off disk or through a
pipe.  And what's optimal for reading files in general may or may not
be optimal for reading Perl source.

• [perl #122955] [PATCH] speed up building with less disk IO pod moves+__END__+misc by Father Chrysostomos via RT
• [perl #122955] [PATCH] speed up building with less disk IO pod moves+__END__+misc by bulk88 via RT
• [perl #122955] [PATCH] speed up building with less disk IO pod moves+__END__+misc by bulk88 via RT
• [perl #122955] [PATCH] speed up building with less disk IO pod moves+__END__+misc by Father Chrysostomos via RT
• Re: [perl #122955] [PATCH] speed up building with less disk IO pod moves+__END__+misc by Craig A. Berry
• Re: [perl #122955] [PATCH] speed up building with less disk IO podmoves+__END__+misc by H.Merijn Brand
• Re: [perl #122955] [PATCH] speed up building with less disk IO pod moves+__END__+misc by Craig A. Berry
• [perl #122955] [PATCH] speed up building with less disk IO pod moves+__END__+misc by Tony Cook via RT
• [perl #122955] [PATCH] speed up building with less disk IO pod moves+__END__+misc by Father Chrysostomos via RT
• [perl #122955] [PATCH] speed up building with less disk IO pod moves+__END__+misc by bulk88 via RT
• [perl #122955] [PATCH] speed up building with less disk IO pod moves+__END__+misc by Father Chrysostomos via RT
• [perl #122955] [PATCH] speed up building with less disk IO pod moves+__END__+misc by bulk88