[datagrid] Performance tests posted by mui-bot are inaccurate

[romgrk]

What's the problem? 🤔

The datagrid performance tests run by the datagrid are quite inaccurate. For filtering, they often even show test runs with negative runtime, and I know I optimized filtering a lot but I probably did not make it fast enough to reverse the flow of time.

So I was wondering if we should either remove the tests, or spend time to make them accurate? It would also be way nicer if they'd show the before/after time, rather than just a flat value for the current branch.

In their current state, I'd remove the tests because they're noise that I never look at due to their inaccuracy and that they don't provide a comparison.

cc @mui/xgrid

[flaviendelangle]

Unfortunately I feel like those tests started with a good intention but were never actually used.
Did anyone compared the results between a PR and master for example?

If we have a better idea on how to benchmark performances, it would be great.
But I agree that the current implementation brings no value.

[romgrk]

Even when I worked on filtering, sorting & grouping performance I didn't rely on those numbers. The big issue is the connection via puppeteer, which is naturally async.