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Re: Curl upgrade from 7.65.1 to 7.70.0 causing performance degradation

From: Ray Satiro via curl-library <curl-library_at_cool.haxx.se>
Date: Wed, 16 Sep 2020 02:46:14 -0400

On 9/14/2020 8:13 PM, Kunal Chandarana via curl-library wrote:
>
> This is continuation of an earlier thread
> <https://curl.haxx.se/mail/archive-2020-09/0016.html>, that was
> addressed to an incorrect audience. Using curl-library mailing for
> further discussion.
>
> I further investigated the issue. As I mentioned earlier, we use the
> connection pause/unpause feature. If the connection is paused then the
> library uses a temporary buffer (pausewrite function
> <https://github.com/curl/curl/search?q=pausewrite&unscoped_q=pausewrite>)
> for holding the data. I noticed that this buffer continues to increase
> (buffer size reaches upto 7mb for 13mb response) and malloc,
> memcpy calls on the buffer of this size causes slowness. Further
> investigation revealed that buffer size increase has been taking place
> since the following change
> <https://github.com/curl/curl/commit/e040146f22608fd92c44be2447a6505141a8a867> was
> introduced in the library. Before this change, we did not notice any
> performance degradation. I compared buffer size before and after the
> change, screenshot attached here. How do you think we can proceed from
> here for fixing this issue?
>

Did you do the things that were recommended, did you try the latest
version and did you then bisect that version? If you revert that commit,
what happens? What is your curl_version()?

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Received on 2020-09-16