Le 2011-07-15 à 16:52, Andrew Kinnie a écrit : > Greetings, > > I have 2 issues, the first of which I had before WOWODC, and the second burst > into the open yesterday. > > I have an app, an ERRest app, acting as a push notification server, although > thus far now push notifications have gone out to the public, it works for > testing. The app is connected to by nearly 50,000 iOS devices which have our > iOS app installed. The iOS app connects to Apple to get a token, then calls > home (my server) and tries to register itself with my server so that when we > do send out notifications, we know which device tokens want which types of > notifications. The iOS apps on individual iOS devices connect when running, > and send information to my server about the device, the id of the device, > other data including the token and whether they want the 4 notification types > to be on or off. All this works. (there are approximately 50,000 registered > application_device rows currently, though we've not sent any publicly visible > notifications). When the app runs, the devices also try and get the last > notification of any type that the device has been set to ask for, and display > that in a drop down (data pulled from my server) > > The server uses ERRest to receive this information and to create a device > (actually an "ApplicationDevice" object) based on passed in json, checks the > database (MySQL) to see if there is an existing row in my application_device > entity/table for the app, and the device id (udid) and if so, updates it with > the newly created device's data before discarding the new device and saving > the changes in the fetched one. Otherwise, it saves the newly created device. > > However, > > 1. Occasionally, two devices try to be created at the same time with the same > primary key (which is provided by the EO_PK_Table in the MySQL database). > The second device fails with an exception. I gather this is because two > separate devices are connecting to the server at approximately the same time, > both asking the EO_PK_Table for the next primary key for the entity, then do > some things, then try and save. First one succeeds, and the second fails > because an object with the PK already exists. I was under the impression > that EOF should handle this, but it doesn't seem to. > > 2. We tried to send out some test notifications yesterday, which exposed some > inefficiencies in my model, which seem to have been resolved, but there are > still significant issues. Apache and MySQL are fine, neither is pressed, but > the CPU approaches 100% usage in spikes on the server (a CentOS VM with 16 GB > RAM running Java 1.6 64 bit). Nothing else is running on it. The individual > queries in the registration process do not return more than 5 rows, though > there are 18 separate SQL calls caused by the registration method, all but > one returns 1 row, and the other returns 5. In any event, MySQL has no slow > queries. > > So it's the WO Java processes that seem to be taking up 100% of the CPU. > Constantly getting worker-thread broken pipe errors when it is pressed like > that.
For the record, yesterday we weren't even able to use jstack to see what was going on. But we did see working threads going up to 128. No stuck queries in MySQL. _______________________________________________ Do not post admin requests to the list. They will be ignored. Webobjects-dev mailing list ([email protected]) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/webobjects-dev/archive%40mail-archive.com This email sent to [email protected]
