> On Feb 4, 2015, at 8:21 PM, Graham Cox <graham....@bigpond.com> wrote: > > Do you or anyone else know if there's some inherent limit to the number of > simultaneous sockets that can be opened? I'm supposing that there's a 1:1 > correspondence between a NSURLSession and a socket, because of the > description against [NSURLSession resetWithCompletionHandler:] says: > > "This method empties all cookies, caches and credential stores, removes disk > files, flushes in-progress downloads to disk, and ensures that future > requests occur on a new socket" > > This implies that there's a socket associated with the session.
Network connections use sockets. Sockets use file descriptors. There is a per-process limit on the number of open file descriptors. You can use getrlimit(RLIMIT_NOFILE, …) to query the limit in your process, and setrlimit(RLIMIT_NOFILE, …) to attempt to raise it. The default limit may be as low as 256, depending on OS version and on how the process is launched. (Note that each two-way network connection uses two file descriptors.) setrlimit() should be able to raise the file descriptor limit to a few thousand unless your system administrator is mean. If you hit that limit you should see errors from various network API. File a bug report if you find some API that causing weird crashes instead of failing gracefully or halting with an appropriate error message when you run out of file descriptors. -- Greg Parker gpar...@apple.com Runtime Wrangler _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
