Saturday, January 14, 2006

of misdirection and other things

I managed to haul the UPS battery pack down to The Battery Bloke shop today not an easy task but taking the car seemed such a waste. The batteries are standard sealed lead acid jobs so no problems sourcing them. All up $140 including the labour involved in removing the plastic terminal covers and connector and attaching said items to the new batteries.

I have been trying to track down some annoying bugs in the page level verified exec stuff. There seem to be a few bugs that have been hiding each other. Once after whacking on what I thought was the right bit of code I eventually work out the bug was in a totally different spot, fixing that bug made one of the crashes go away. I hate that, you have a segment of code you are not certain about and are sure there are bugs lurking in there so you start whacking away. After a concerted effort you work out that the bit of code is not involved at all in making things crash. Now I am at the point where things work exactly twice, on the third time the kernel either panics or weird stuff happens. The problem is that the panic or weird stuff happen in a sort of unrelated place - the damage is done elsewhere but it only circles around and bites later on which is rather difficult to debug. Again, for a long while I thought the problem was with the way I was releasing pages but even totally disabling the page release code does not stop the kernel panic, the fault lays elsewhere in the code. I shall try just removing code until things start working so I can narrow down what is being done incorrectly. Tedious.