ncsim out-of-memory when enabling code coverage

Hi everybody,
this is my first post in the forum and I hope I'm writing in the right section.

My group is using a specman-based verification environment to test a small system composed of 2 IPs. Additionally, we use nc-coverage to collect data on block, expression and FSM coverage.

At this moment our most intensive runs are based on three different tests, each executed 80 times with a random seed. This scenario will be further complicated in the near future.

Multiple test runs are controlled with the ncsim Tcl shell, using some custom procedures. Note that only one instance of the simulator is run. Basically, at each iteration, we perform the following tasks:

foreach test $test_list {
- specman: load a specific test
LOOP on test runs
- ncsim: reset the simulator
- specman: reload environment
- specman: test -seed=random
- ncsim: setup coverage:
    * coverage -setup -dut :
        * coverage -setup -testname [format "%s_run%s" $test_name $tag]
        * coverage -setup -workdir [file join $outdir nc_cov_data]
        * coverage -code
        * coverage -fsm
- ncsim: run
- ncsim: dump coverage data
    * coverage -code -dump
    * coverage -fsm -dump
- update counters for next iteration
END LOOP
} # close loop on tests

Simulations run fine if code coverage is disabled (not instrumented during elaboration), but goes out of memory when enabling code coverage. Memory reduction can also be achieved by reducing the sample rate of code coverage (i.e. every 10 test runs, instead of all test runs)

In my understanding, all simulation runs are independent and simulator should flush data between each reset/reload. However, it seems that memory occupation increases after each test run until the max_size limit is reached.

I think that a possible solution could be moving the loop from the simulator shell to an external system shell, in this way each test run would require starting and shutting down ncsim. This would also require re-arranging our script system, which is something I'd like to avoid as we're planning to move to Enterprise Manager in january.

Any suggestion for a fast-fix?

I'm using IUS5.5 and Specman 5.0.3 eVCs are compiled in a shared library and linked to ncsim_specman with the SPECMAN_DLIB variable. IPs are developed in VHDL.

Thank you very much,
nico