[m-rev.] for review: reduce the parser's memory consumption

[Julien Fischer]

On Fri, 2 Aug 2019, Zoltan Somogyi wrote:

> For tryout and review by Julien. My laptop's timing variability is bigger
> than the performance effect of this change; I hope you can measure its impact
> using Opturion's server class machines.

Sure, did you have a specific test in mind?

Julien.