URLSession seems to really be broken on iOS 10 (compared to iOS 9). I am constantly getting "too many files open" errors now (both device and simulator), and I also am seeing "A server with the specified hostname could not be found" after a time. The latter goes away if I restart the simulator. I don't know if I'm seeing this on the device. I know the hostname is fine because all my downloads are to the same host, and many of them complete. I used to set up thousands of downloads per session, but now I'm throttling it to 4 at a time per session. One or two simultaneous sessions seems okay, but between 5 and 11, I start to get the "too many open files" problem. This is concerning. Note that a single session, even with a thousand downloads, seems to work okay. A very large session can fail though. Radar 29280854 -- Rick Mann rmann@latencyzero.com _______________________________________________ Do not post admin requests to the list. They will be ignored. Macnetworkprog mailing list (Macnetworkprog@lists.apple.com) Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/macnetworkprog/site_archiver%40lists... This email sent to site_archiver@lists.apple.com