Stalking the infinite loop

Today began with an effort to track down the infinite loop which is causing the java process to munch CPU cycles on the portal server. The problem seems to be spreading.. when I checked this morning around 6:30am, there were 4 looping threads on uportal1 and 5 on uportal2. I’ve tracked down the offending loop, and I started out by putting a counter into it and logging the number of times the loop ran after each successful completion. This gave me a pretty good idea of how many times we should go through the loop under normal circumstances (looks like only 2 or 3). Then I picked an arbitrary large number, 1000, and changed the code so it throws an exception if the counter exceeds this value. I’m hoping this will have two effects: one, stop the looping; and two, provide some logging so we can further investigate what is causing the problem. The new code is up and running, so we’ll see how it goes.

Welp, it worked. Interesting… very similar to yesterday, everything was quiet all morning and then both instances hit the infinite loop almost exactly at 1pm. Now, instead of an endlessly looping thread, I get a nice error log and stack dump. Next thing to do is try to log some additional info, to see if I can narrow this down to a particular user, activity, or whatever. If this is only affecting certain user(s), maybe someone will call the help desk and help me solve the mystery.

Other than that, the biggest issues so far have been related to permissions and affinities. Lots of people complaining that they don’t see content they used to get on the old portal. I expected this, because the uPortal groups/permissions model is quite different from what we were using with the old myUMBC. For now, I’m noting the users who are having problems, and in a week or so I’ll call a meeting to discuss how to reconcile them. In the meantime, these users can continue to use the old portal.

I also discovered today that the new portal does not work for anyone who has a “mandatory PIN change” flag set in SIS. Now first off… PINs are going away. There’s nowhere in myUMBC where a user is required to enter a PIN any more (well, there’s orientation.. but don’t go there). Given that, I made the executive decision that mandatory PIN changes are going to go away in uPortal, and tweaked the legacy code accordingly. However, it looks like the HP is checking the forced_pin_change field and disallowing registration if it is set. So it looks like I need to take this one step further, and actually submit a PIN change for these users behind the scenes. Looking into that now. Regardless, we’re definitely going to need to test how the portal behaves with “virgin” users, before the fall semester starts.

My God, I’m going through my own code that does the HP PIN stuff, and it is so bloody convoluted I want to shoot myself. From following the code, I can’t see any way for it to ever get to the HP PIN verify when accessed normally. I think what we need is a rewrite that takes all of the PIN stuff out of the normal login process, and doesn’t do anything with PINs until the user does something that accesses the HP. Then, if the user doesn’t have a PIN it can have the HP create one, then send a PIN change request to the HP so it clears out the forced_pin_change flag. Will look at that tomorrow..