git: test - Add various 900,000 process tests

Michael Neumann mneumann at
Tue Aug 15 02:14:07 PDT 2017

On Monday, 14 August 2017 23:13:27 CEST, Matthew Dillon wrote:
> commit b5daedd44b0cb06b9a9df40d3288467b31d0b5e1
> Author: Matthew Dillon <dillon at>
> Date:   Mon Aug 14 14:03:57 2017 -0700
>     test - Add various 900,000 process tests
>     Add tests involving a large number of user processes.  
> These tests default
>     to creating 900,000 user processes and require a machine with at least
>     128GB of ram.  The machine must be booted with kern.maxproc=4000000 in
>     /boot/loader.conf.

I wonder why we need 128GB of ram for 900,000 processes? That is ~142 MB 
process. Does the kernel have to preallocate so much to support that high
number of processes?

The pipe900k test is pretty cool... measuring the latency of 900k piped 
processes :).
I wonder how other operating systems would perform under that test, or 
abstraction layers like MPI (message passing interface).



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