Created attachment 469596 [details] Safari upload speeds limited Problem: Safari upload speeds limited to 5500-6700 Mbps I set MTU to 1500 MTU, Achieves full speed for upload when I set MTU to 9000. Download speeds unaffected and reach full 10Gbps. Chrome Comparison: Chrome achieves full 10Gbps for both download and upload with both standard and jumbo MTU sizes. Version 17.3 (19617.2.4.11.8) Version 14.3 (23D56)
To reproduce this issue, run OpenSpeedTest Server (Docker or MacApp) on a machine with 10GbE network connection. Connect another machine with 10GbE directly to the first machine or a network with 10GbE, and then run a speed test using Safari.
@Alexey - Would it be at WebKit level or Core Services and should this be moved?
It is not clear to me if this is different from bug 251328. This is really best to report via Feedback Assistant with a sysdiagnose. But importing to make the right people aware.
<rdar://problem/121940949>
It was only observed for HTTPS at that time. However, this behavior is now also occurring for HTTP. I used M1 MacMini with 10GbE.