Make use of massive qgis_process speed-up in upcoming QGIS >= 3.36

[florisvdh]

See qgis/QGIS#54563.

Most of the performance gains made at the QGIS side don't need an update from our side, i.e. with QGIS 3.36 the qgis_process calls just have much less overhead 🚀 . (Currently the updates are implemented in QGIS 3.35)

However there's one feature we must actively take advantage of: the --skip-loading-plugins flag – see qgis/QGIS#55794, including timings – for commands:

• qgis_process plugins
• qgis_process help: only do --skip-loading-plugins for algorithms from the 'processing' plugin (the built-in algorithms)
• qgis_process run: only do --skip-loading-plugins for algorithms from the 'processing' plugin (the built-in algorithms)

The speedup with vs without --skip-loading-plugins is almost x2 !! Add to that the several speedups already implemented and referred to by qgis/QGIS#54563.

In qgis_process plugins {enable,disable} <plugin> using the flag does not make a difference.

Using the flag in older QGIS versions results in an error, so using the flag must depend on the QGIS version!

--------- Many credits to @nyalldawson for the various speedups 🙏 ; INBO is proud to support these.