Automon

Serial Thread Priority

After adding the dials for representing sensors in a more graphical way, random serial I/O problems occured resulting in incorrect figures being obtained.

The solution was to increase the priority of the serial I/O thread to higher than the rest. By default it inherits the same priority from the calling thread but this isn’t enough.
I started my thead with the QThread::TimeCriticalPriority enumerated type. This seems to have solved the problem. If I discover any more problems, i will attempt setting the whole processor priority higher using the Linux nice command.

The QT Thread priority types are:

QThread::IdlePriority	0	scheduled only when no other threads are running.
QThread::LowestPriority	1	scheduled less often than LowPriority.
QThread::LowPriority	2	scheduled less often than NormalPriority.
QThread::NormalPriority	3	the default priority of the operating system.
QThread::HighPriority	4	scheduled more often than NormalPriority.
QThread::HighestPriority	5	scheduled more often than HighPriority.
QThread::TimeCriticalPriority	6	scheduled as often as possible.
QThread::InheritPriority	7	use the same priority as the creating thread. This is the default.