Somehow it takes 4 seconds to un-collapse a toplevel comment in Chrome. E.g. this one:
https://teddit.net/r/Bossfight/comments/k6vh5v/bearers_of_th...Pages also seem to take around 10 seconds to do the initial render. No server problem, just rendering.
So if you do use this, I guess don't overdo it. :) Or at least profile.
I use a 2015 MBP potato laptop. I guess my perf problems aren't really relevant. But it handles all modern sites just fine, so it was surprising.
Definitely spikes something to 100% on each load: https://i.imgur.com/1fqBDEX.png and the CPU graph is a nice timeline of me reloading teddit.
EDIT: Oof. I just did a profiling session to figure out what the heck it was doing:
https://imgur.com/ilvRkEb
Purple = rendering time. As you can see, it's 100% pegged at rendering whenever I uncollapse a thread.
So, devs, if you happen to read this, the process is:
1. go to https://teddit.net/r/Bossfight/comments/k6vh5v/bearers_of_th...
2. Collapse the toplevel comment https://imgur.com/vjDhTk2
(which is very fast.)
3. Activate a profiling session: Command-option-I, click performance tab, command-E to start recording
4. Un-collapse the thread
5. Stop recording
Here's the profiling session in case it helps: https://battle.shawwn.com/misc/2020-12-04/Profile-20201204T1... No idea if it gives any insight into what's going on, but there y'go.
I'm not sure how they'd solve this. 98.2% of the time is spent in "Layout": https://i.imgur.com/tSexr0n.png
Is there even anything you can do to address that kind of perf problem? Yuck. I don't envy whoever digs into that one.
I tried profiling with "Enable advanced paint instrumentation (slow)" but it seemed to show exactly the same result:
https://i.imgur.com/V26oOTT.png
"Nodes That Need Layout 3841 of 3987 Layout root#document" seems relevant. So it sounds like the details card is somehow causing a full-page layout for almost every element on the page. Which should be fast, except that every element seems to cause another layout. Or ... something.
Not sure if there's any other details I could give, but let me know if anyone has ideas.