> cat $HOME/big_file | filter1 | filter2 | filter3 > $HOME/output
>
> That leads to having 4 processes, each of which can (and likely
> will) migrate to separate CPUs.

Instead use:
< $HOME/big_file filter1 | filter2 | filter3 > $HOME/output
which requires only 3 processes to accomplish the same thing.

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