hamilton
commented
6 years ago We dug into this a bit today to see what might be causing this issue. Here are our theories:
- "run all cells" creates a big Promise chain, each promise being a cell evaluation. Possibly something about the microtasks gets in the way of repaint. This, however, is probably not the case. For one thing, I tried appending to the DOM at various places within the actions to see if they drew all at once. All the DOM elements appeared before the big batch update of all the components, so there doesn't appear to be a paint issue. Furthermore, I tried also removing all Promises, and the issue still seemed to persist.
- something in how React batches updates is causing the whole thing to wait in Chrome, but not in FF.
We'll have to dig in a bit more to see what's going on.
bcolloran
try loading the following in FF and Chrome: https://iodide-project.github.io/iodide-examples/lorenz-attractor-pres.html
In FF, the MD cells render, then the JS stuff updates (as expected) In chrome, after a delay, everything shows up in the viewport in it's final state
i wonder if this has to do with different handling of task queues and schedules under different browsers https://jakearchibald.com/2015/tasks-microtasks-queues-and-schedules/
see also the stack overflow links https://github.com/iodide-project/iodide/issues/587 about not being able to update the dom within a loop. i wonder if an easy fix would be to have a little setTimeout of a few ms in the eval queue before each eval to "hand control back to the browser" for updating the DOM