How to understand the run_phase in the uvm test

In reply to chr_sue:

In the run_phase of my_test, I tried to start the sequence as shown below.

task my_test::run_phase(uvm_phase phase);

super.run_phase(phase);
phase.raise_objection(this);
wait_cycle(100);    // customized task...
my_sequence my_seq;
......
my_seq.set_starting_phase(phase);
my_seq.start(...);
phase.drop_objection(this);

endtask : run_phase

Actually I set a breakpoint at phase.raise_objection in the run_phase above. But it never is reached…

Thank you !!!