Ninety Nine Percent Trick

An MLFQ scheduler uses these rules:

• Rule 3: a new job enters at the highest priority.
• Rule 4a: a job that uses up its 10 ms allotment while running drops one queue.
• Rule 4b: a job that gives up the CPU before the allotment is up stays at the same priority, and its allotment is reset.

A user writes a job that runs for 9.9 ms, issues a one-byte write to a file, then loops.

slice	CPU used before yielding	allotment used at exit	queue after
1	9.9 ms	reset to 0	top
2	9.9 ms	reset to 0	top
3	9.9 ms	reset to 0	top

What does this job do to the CPU-bound jobs sitting in the lower queues?