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Re: setup

On Jun  9 18:54, Achim Gratz wrote:
> Corinna Vinschen writes:
> > Right, in the networking case the download should be the major factor,
> > but I was referring to the SSD case.
> >> > Can you speed up reading the ini file noticably by defining
> >> > YY_READ_BUF_SIZE to 65536 in inilex.ll?  If so, is the impact of using
> >> > base64 still an issue, performance-wise?
> >> 
> >> That's not the right place to do the override, since it ends up after
> >> the default definition.
> >
> > Huh?  Not for me:
> I had been trying to put it before the includes and that buggered up
> things.  Ain't that wonderful?
> >> In any case, from the Flex manual it doesn't
> >> make sense to increase that buffer ("it's almost always too large") and
> >> it is being fed from an io_stream, which is buffered itself.
> >
> > Yes, but it's using the default buffersize of the underlying MSVCRT
> > stdio, which is using some value I don't know off the top of my head.
> > Typically this would be 1K or 4K.  YY_INPUT is reading in 8K chunks, so
> > the underlying stdio is very likely already skipping its buffering.
> > So changing YY_READ_BUF_SIZE to 64K *should* have an impact.
> It still looks that the loading of the file is the culprit and not the
> parsing, but it's hard to make out the difference on that system here.
> In any case, setup now manages to write to SSD with about 15MiB/s on
> average and about 40MiB/s tops (using the gcc-debuginfo package since
> that has a good mixture of a few very large files and many small files).

I'm a bit puzzled at this point.  Changing YY_READ_BUF_SIZE wouldn't
change unpacking tar files.  What am I missing?

Either way, please go ahead and apply your patch.  While you're at it,
would you mind to change YY_READ_BUF_SIZE as above and raise the buffer
size in io_stream::copy to 64K as well?


Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Maintainer                 cygwin AT cygwin DOT com
Red Hat

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