result.txt

timo@schmand /tmp> perl6 --profile=heap testshellmem.p6 shell
Before shell call : 101.664 kb
html is 230457 chars
After shell call : 210.332 kb
After forced gc: 249.704 kb
html is 230457 chars
After shell call : 323.016 kb
After forced gc: 354.232 kb
html is 230457 chars
After shell call : 401.640 kb
After forced gc: 418.024 kb
html is 230457 chars
After shell call : 418.024 kb
After forced gc: 418.024 kb
html is 230457 chars
After shell call : 418.088 kb
After forced gc: 418.088 kb
html is 230457 chars
After shell call : 418.152 kb
After forced gc: 418.152 kb
html is 230457 chars
After shell call : 418.152 kb
After forced gc: 418.152 kb
html is 230457 chars
After shell call : 418.152 kb
After forced gc: 418.152 kb
html is 230457 chars
After shell call : 418.152 kb
After forced gc: 418.152 kb
html is 230457 chars
After shell call : 418.152 kb
After forced gc: 418.152 kb
After sleep 5 : 418.152 kb
Heap snapshot written to heap-snapshot-1504868482.9648
timo@schmand /tmp> mv heap-snapshot-1504868482.9648 heap-snapshot-shell-sub
timo@schmand /tmp> perl6 --profile=heap testshellmem.p6 qqx
Before shell call : 101.776 kb
html is 230457 chars
After shell call : 180.612 kb
After forced gc: 216.272 kb
html is 230457 chars
After shell call : 285.692 kb
After forced gc: 310.268 kb
html is 230456 chars
After shell call : 387.244 kb
After forced gc: 411.820 kb
html is 230457 chars
After shell call : 411.820 kb
After forced gc: 411.820 kb
html is 230456 chars
After shell call : 412.140 kb
After forced gc: 412.140 kb
html is 230457 chars
After shell call : 412.140 kb
After forced gc: 412.140 kb
html is 230457 chars
After shell call : 412.144 kb
After forced gc: 412.144 kb
html is 230457 chars
After shell call : 412.144 kb
After forced gc: 412.144 kb
html is 230457 chars
After shell call : 412.144 kb
After forced gc: 412.144 kb
html is 230456 chars
After shell call : 412.160 kb
After forced gc: 412.160 kb
After sleep 5 : 412.160 kb
Heap snapshot written to heap-snapshot-1504868530.9759
timo@schmand /tmp> mv heap-snapshot-1504868530.9759 heap-snapshot-qqx
timo@schmand /tmp> perl6 --profile=heap testshellmem.p6 run
Before shell call : 101.604 kb
html is 230457 chars
After shell call : 211.148 kb
After forced gc: 249.548 kb
html is 230457 chars
After shell call : 318.508 kb
After forced gc: 343.084 kb
html is 230457 chars
After shell call : 394.464 kb
After forced gc: 410.848 kb
html is 230456 chars
After shell call : 410.848 kb
After forced gc: 410.848 kb
html is 230457 chars
After shell call : 410.992 kb
After forced gc: 410.992 kb
html is 230457 chars
After shell call : 411.248 kb
After forced gc: 411.248 kb
html is 230457 chars
After shell call : 411.248 kb
After forced gc: 411.248 kb
html is 230457 chars
After shell call : 411.248 kb
After forced gc: 411.248 kb
html is 230456 chars
After shell call : 412.272 kb
After forced gc: 412.272 kb
html is 230456 chars
After shell call : 413.172 kb
After forced gc: 413.172 kb
After sleep 5 : 413.172 kb
Heap snapshot written to heap-snapshot-1504868591.0786

testshellmem.p6

use Linux::Proc::Statm;

sub mem($a) {
  say $a ~ get-statm<data>.flip.comb(/.**1..3/).join('.').flip ~ ' kb';
}

mem("Before shell call : ");

my $html;
if @*ARGS[0] eq "qqx" {
 $html = qqx{wget -o /dev/null -O - https://www.fimfiction.net/bookshelf/149291/};
}
if @*ARGS[0] eq "shell" {
  my $proc = shell "wget -o /dev/null -O - https://www.fimfiction.net/bookshelf/149291/", :out;
  $html = $proc.out.slurp;
}

if @*ARGS[0] eq "run" {
  my $proc = run "wget", "-o", "/dev/null", "-O", "-", "https://www.fimfiction.net/bookshelf/149291/", :out;
  $html = $proc.out.slurp;
}

say "html is " ~ $html.chars ~ " chars";
mem("After shell call : ");

sleep 5;
mem("After sleep 5 : ");