Memory Leak in LDV 4.1 and 5.1 when using Restart?

[Chris]

I've noticed what appears to be a memory leak in LDV 4.1 and 5.1 running
on both Linux and Solaris 32 bit machines. I'm not sure if this
intentional, but it appears that everytime a restart is called from the
tcl command interface, memory is not cleared. Consequently saving a
checkpoint and restarting from this checkpoint several times (on the
order of thousands) eventually leads to out of memory errors in the
operating system. I've noticed if the simulation is exited and then
restarted from the last saved checkpoint, the memory usage appears to be
back to the original when the checkpoint was created. Anyone else run
into this and have any more info on it? I realize that most users
probably do not run this many restarts however it is necessary for my
testing. I've attached a sample code.

--Chris

verilog file:
-------------
`timescale 1ns/1ns

module test;
integer a;
initial begin
a = 1;
end
always begin
#1 a = a + 1;
if (a == 10000) begin
$display("A");
end
end
endmodule


sim.tcl file for save/restarting:
---------------------------------
set LATENCY 1000

# CREATE CHECKPOINT
run -clean
save -overwrite chkpt
run $LATENCY ns

# Loop continuously restarting from checkpoint each iteration
while {1} {
for {set j 0} {$j < 1000} {incr j} {
restart chkpt
run $LATENCY ns
}
set i [expr $i+1]
puts [format "CHKPT %d" $i]
puts [eval status]
}
finish


SAMPLE OUTPUT (Notice the "data" increases with each 1000 restarts)
-------------------------------------------------------------------
CHKPT 1
Memory Usage - 18.2M program + 2.8M data = 21.0M total
CPU Usage - 0.8s system + 1.4s user = 2.2s total (70.4% cpu)
Simulation Time - 1001 NS + 0

CHKPT 2
Memory Usage - 18.2M program + 3.1M data = 21.3M total
CPU Usage - 1.4s system + 2.2s user = 3.6s total (69.7% cpu)
Simulation Time - 1001 NS + 0

CHKPT 3
Memory Usage - 18.2M program + 3.5M data = 21.7M total
CPU Usage - 2.1s system + 3.0s user = 5.1s total (68.1% cpu)
Simulation Time - 1001 NS + 0

CHKPT 4
Memory Usage - 18.2M program + 3.9M data = 22.1M total
CPU Usage - 2.8s system + 3.8s user = 6.6s total (68.3% cpu)
Simulation Time - 1001 NS + 0

CHKPT 5
Memory Usage - 18.2M program + 4.3M data = 22.5M total
CPU Usage - 3.5s system + 4.6s user = 8.0s total (67.3% cpu)
Simulation Time - 1001 NS + 0

CHKPT 6
Memory Usage - 18.2M program + 4.7M data = 22.9M total
CPU Usage - 4.1s system + 5.3s user = 9.5s total (67.5% cpu)
Simulation Time - 1001 NS + 0

CHKPT 7
Memory Usage - 18.2M program + 5.1M data = 23.3M total
CPU Usage - 4.8s system + 6.1s user = 10.9s total (67.6% cpu)
Simulation Time - 1001 NS + 0

CHKPT 8
Memory Usage - 18.2M program + 5.5M data = 23.7M total
CPU Usage - 5.5s system + 6.9s user = 12.4s total (67.0% cpu)
Simulation Time - 1001 NS + 0