So, you can actually execute that piece of code to dl a large file (~100MB+) and have it copied directly to a file, without using a portion of memory directly proportional to file's size?

I did 38M/135M and , the memory never grew past 10M. For server (never past 12M) I used

 plackup -l localhost:80 -e " use Plack::App::Directory; my $app = Plack::App::Directory->new({ root => q[.] })->to_app; "

Can you spot something wrong with my code?

Nope, I don't see any mistakes but on linux (BREWED) makes me think maybe you're using a fudgy malloc? Kinda unlikely but I've seen folks complain about it :) I'm on win32 so you probably can't compare my Config:)

$ perl "-V:.{0,}alloc.{0,}"
d_attribute_malloc='undef';
d_malloc_good_size='undef';
d_malloc_size='undef';
d_mymalloc='undef';
i_malloc='define';
i_mallocmalloc='undef';
mallocobj='malloc.o';
mallocsrc='malloc.c';
malloctype='void *';
usemallocwrap='define';
usemymalloc='n';
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