Safari and super slow after Big Sur update

I updated to Big Sur this morning and Safari is almost unusable due to being super slow

cleared cache, extensions. Doesn’t help

any ideas?
  • I'm having this problem too on several Macs, but sporadically. I've noticed that when it occurs, that umount appears in the Activity Monitor spiked at 100% cpu. I am unable to kill the process even with force quit or kill -9. After the process eventually crashes, safari goes back to normal.

    If anyone else is still experiencing this issue, can you check your activity monitor to see if umount is running?

  • TLDR; Try disabling Time Machine or removing faulty Time Machine targets.

    After working on this for awhile, I think I've figure out what's causing the issue that I'm seeing with umount and Safari. Each time that umount is stuck and Safari is non-responsive, Time Machine was failing to access a disk over the network. I've seen it both with a Synology Time Machine share and a Mac OS Server Time Machine share. Removing the faulty Time Machine target or disabling Time Machine altogether appears to result in the issue no longer happening. I hope that this helps at least some of you.

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I have the same problem with MacBook Pro 2020 - M1, 16Gb of RAM.

I open Safari, click the address bar, start typing, everything blocks for a second, then address bar gets filled with 1-2 second delay.

Awful, I have everything latest, machine and the system - please don't make me stop using Safari after 15 years :(

Monterey 12.1 ... I am on optical internet 50Mb/s optic.... trying to upload image of proof AN ERROR HAS OCCURED TRY AGAIN LATER. appeared on this forum.

in Safari apple.com took me 18s to load. Facebook.com took me 30s to load ... and currently downloading Edge to compare if this shit is on this MACBOOK PRO M1 only ... Because on the same router are connected more device and non of them has the same problems as me. Even my 10y laptop loads quicker than default M1 PRO tuning Safari ... considering that 200e beats 3000e laptop gives Apple really bad odds.

Again in Safari I was able to run speedometer.sk pumping up 50+Mb/s speeds with latency 10ms .... So the trouble is not outside of this laptop.