When Is A Leak Not A Leak

I was sent a bug report on some software I had written a while back wherein it would become less and less responsive over time till it just sort of died. Sounds like a leak.


But when I hooked it up to the Leaks Instrument, I saw no leaks. No red peaks at all. Must not be a leak then.


But one more look. The net objects allocated were going up and up and up. This should not happen, the application should have reached an equilibrium point of net objects allocated, and oscillated around it.


So, I let it run for a while in the Objects Allocated instrument, and then examined the blocks which were being allocated and not deallocated. Turns out I had an object, an audio player, which had a scheduled NSTimer associated with it. When I released the player, it was still being referred to by the NSTimer, so it did not get deallocated. And in this case, I was creating one of these every second or so (probably not a good idea), which meant that not only was the memory leaking, but all those timers were adding overhead to the event loop. No wonder it crawled to a halt. So remember to invalidate unwanted timers.

The Loss of Homogeneity: iPhones on the Network

Developing for the iPhone and iPod Touch is nice: limited hardware differences leads to reliability. If it works on my iPhone running the 2.1 OS, it should run well on your iPhone. They are pretty much the same. Homogeneity is good when it comes to testing for program errors.


So your iPhone is the same as mine, but your network is not.

I submitted a new version of Remote Remote GH for OS X Touch to Apple a week ago. It had been gradually gestating and stabilizing has I had time to improve it. The last several weeks, it had been quite stable, and had never been much of a crasher to begin with. Thursday night, Apple notified me that the new version was available for distribution on the App Store; Friday morning RRgh crashed on me on launch. Wha?

Backing up. I had been playing with the XBox Media Center (XBMC) for the AppleTV, and last night I had tried turning on its UPnP (Universal Plug and Play) server and client. The new RRgh's big feature is support for auto-detecting MythTV frontends via UPnP, so having another UPnP device on my network meant my code had to check to see it wasn't a MythTV. Unfortunately, this revealed a latent crashing bug where I was expecting a string, got a NULL pointer instead, and boom, boom crash. (No actual audio percussion, just a silent quit.)

An early updater experiencing (what I assume is) the same problem figured out my e-mail address and let me know that I wasn't the only one.

So, I had to quickly remove RRgh from distribution pending a 1.1.1 release, as I have no wish to get a deluge of negative reviews from whatever small fraction of the populace would be affected by this. Which means, there is no RRgh currently available for download, as I don't have the option to revert to the 1.0 binary.

If you are one of the people who downloaded 1.1, I hope it isn't crashing on you, but I've submitted an updated binary which should be out within the week.