It was me who reported it back then. The precision loss of the rated downloads was more than 10% in some cases, which was above our 5% tolerance.
It caused problems in multi-download prioritized scenarios where rated downloads with less priority were stealing bandwidth from the downloads with higher priority. I am also concerned about CPU usage, but 10% rate precision deviation is too high. And in our case (video streaming application), the problem was that the prioritized video got worse quality and other problems which affected our users. Ideally, the optimal solution would be to avoid busy loops and using too many CPU cycles, and provide 5% rate accuracy. Thanks! Dmitry Karpov -----Original Message----- From: curl-library <[email protected]> On Behalf Of Gleb Smirnoff via curl-library Sent: Tuesday, October 28, 2025 11:11 AM To: Daniel Stenberg <[email protected]>; Stefan Eissing <[email protected]> Cc: Gleb Smirnoff <[email protected]>; Gleb Smirnoff via curl-library <[email protected]> Subject: [EXTERNAL] Re: CPU usage since 8.7.1 On Tue, Oct 28, 2025 at 05:32:27PM +0100, Daniel Stenberg wrote: D> On Tue, 28 Oct 2025, Gleb Smirnoff via curl-library wrote: D> D> > So here I am raising this question. What needs to be done to get D> > CPU savings of 8.6.0 level and how can we help here? D> D> As recall things, the change that introduced the new (current) D> behavior was done to enhance the accuracy of the rate limit logic, at D> the expense of CPU. D> D> The change was pushed for by someone who argued that the increased D> precision was valuable for them if I remember correctly. D> D> Can we find a way to have both ways and let the user select which? D> Maybe for example by maybe something as silly and simple as doing D> CURLOPT_MAX_RECV_SPEED_LARGE % 10000 and if that is non-zero, higher D> precision is wanted. I added Stefan to explicit Cc. Since he very recently added 24badd29f titled "limit-rate revisited" (of course this conlicted with out patch again), he definitely should have an opinion on how this can be solved. -- Gleb Smirnoff -- Unsubscribe: https://lists.haxx.se/mailman/listinfo/curl-library Etiquette: https://curl.se/mail/etiquette.html -- Unsubscribe: https://lists.haxx.se/mailman/listinfo/curl-library Etiquette: https://curl.se/mail/etiquette.html
