Plack::Middleware::MemoryUsage is middleware for measuring process
memory.

Enabling Plack::Middleware::MemoryUsage causes huge performance
penalty.  So I HIGHLY RECOMMEND to enable this middleware only on
development env or not processing every request on production using
Plack::Middleware::Conditional.

WWW: http://search.cpan.org/dist/Plack-Middleware-MemoryUsage/