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Re: Windows users! Help us test upload performance tuning?

From: Daniel Stenberg via curl-library <>
Date: Tue, 14 Aug 2018 09:39:21 +0200 (CEST)

On Tue, 14 Aug 2018, Jan Ehrhardt wrote:

> my tests indicated that increasing this value also influenced the FTP upload
> speeds. From 10 to 5 seconds on XP in Daniel Jelinski's testcurl uploads.
> And down to less than a second on Win 7 and Win 10.

Right. So yes, there's certainly a valid reason to consider and work on upping
the upload buffer size for all protocols. I suppose we simply haven't done
enough upload speed comprisons and tests recently...

If plain FTP uploads can go faster with a larger buffer, that's an indication
that *all* TCP protocols can be done faster if given larger buffers. (At least
on Windows.)

How much larger buffer is sensible? If we're talking about changing the
default size. The current buffer size has been used since basically day 1 and
both the Internet and devices that run curl have changed a bit since then...

It would probably still be valuable to allow applications to set the upload
buffer size a similar way it can set download buffer size. Or should we even
set the upload buffer to the same size as that one?

I think its time we run some tests in an orderly fashion with different upload
buffer sizes and collect some numbers...

Received on 2018-08-14