Why is Json parsing slower in multiple threads?

[Alexandre Bourquelot]

On Tuesday, 20 June 2023 at 10:29:04 UTC, Kagamin wrote:
> The program does 3 times more work and gets it done in 3 times 
> more time: 1.5*3=4.5

Thanks for your reply.
I am using threads so the work should get done in the same time 
that it takes for one file to get processed, since its 
distributed across cores.

I even wrote a similar C++ program just to be sure, that performs 
as expected.