There is no need to create your own queue. The SAM server creates the queues internally, and then feeds the alarms one at a time into the ASL script. Once the START rule is complete, then the next notification will be processed. So, if you do not write an efficient ASL script then it becomes a bottleneck and the queues in SAM build up, using up memory, and subsequent crash.
The only way that you can speed up the processing is by having multiple notification lists feeding multiple ASL scripts.