> On Nov 22, 2016, at 16:47 , Shawn Erickson <shaw...@gmail.com> wrote: > > I am kinda curious if you can put together some example code for the problem. > > I am hitting a single URL session with 10 concurrent requests driving thru > hundreds in a minute for small requests against the same backend. I throttle > things using an operation queue set to 10 current operations and have a > simple asynchronous friendly operation starting up the request and finishing > it self when the operation competes. > > I have run up the concurrency as a test and not seen what you are reporting. > > As others note it really isn't a good idea to attempt that many concurrent > requests in the same URL session or different session especially if hitting > the same server. Unless the server is returning data very very slowly with no > bandwidth limits between you and it you likely shouldn't have more then a > handful active at once.
Again, I hit the problem with only 4 (or with the default settings), and 5 - 11 simultaneous URLSessions. And again, I don't have this problem at all on iOS 9. I might be able to build a test case that hits our servers, but it does require downloading thousands (perhaps hundreds) of files per session. > > -Shawn > > > On Tue, Nov 22, 2016 at 1:29 PM Rick Mann <rm...@latencyzero.com> wrote: > > > On Nov 22, 2016, at 03:23 , Quinn The Eskimo! <eski...@apple.com> wrote: > > > > > > On 22 Nov 2016, at 11:17, Rick Mann <rm...@latencyzero.com> wrote: > > > >> I tried setting it to 4, but I still get the problem. > > > > What happens if you don’t modify it at all? > > Still get the problem. > > FWIW, I'm also setting .httpShouldUsePipelining to true and > .timeoutIntervalForRequest to 3600 (necessary because the timeout isn't reset > for each request, but rather for the whole session). I commented out all my > adjustments and tried just the default URLSessionConfiguration, still the > same behavior. > > • Aside: I was getting the default URLSessionConfiguration and setting these > properties. Should I be getting a copy of the default instead? > > • I'm also worried about the frequent "A server with the specified hostname > could not be found" errors I get. Could that be the result of attempts at DNS > resolution failing because of too many open files, and being changed into a > not-found error? I also get "The Internet connection appears to be offline". > > In fact, all three errors are often found interspersed throughout. > > • I don't understand why so many connections are opening, since I am > currently limiting it to 4 tasks per session. It seems they're not closing > after each use, but not getting re-used? > > Thanks, > > -- > Rick Mann > rm...@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/shawnce%40gmail.com > > This email sent to shaw...@gmail.com -- Rick Mann rm...@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/archive%40mail-archive.com This email sent to arch...@mail-archive.com
