Dear Bryntum team,
We noticed some performance degradation upgrading the Scheduler component from 3.0.4 to 4.0.7. We observed that with 150 events (10 resources, each with 15 events) the time required to render all the events on the UI is doubled (from 1 sec to 2 secs).
We've noticed there's a similar bug opened and solved on performances (viewtopic.php?f=51&t=16127). So we tried the latest nightly build (with the fix) but we still have the same bad performances.
Just to add some more info, we're using a custom "eventRenderer" and we're using the startBatch/endBatch. Even removing them as suggested in the thread mentioned above didn't change the things. Having a look the the Chrome Performance tool we also observed something weird that was not happening in Scheduler 3.x.x: "onElementResize" is triggered automatically and it's re-calculating all the HTML templates. This step alone is taking more or less 700ms and we don't have any clue about why and who is triggering it.
I'll attach some files like the performance data from Chrome Performance tool. All the measures have been taken on the same machine with Chrome 88.
Please let me know if you need any further info,
Giovanni