I have a late 2019 macbook pro (the base model). I've been running Catalina until yesterday when I upgraded to Big Sur 11.2.2. It's noticeably laggy. Has anyone experienced this? I'm not sure if 11.2.1 was laggy, so I was considering downgrading. Does anyone know how I can downgrade to 11.2.1, and possibly back to Catalina?

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    Why not focus on one question per question? If you have lag - define precisely what you are measuring and if it’s CPU - maybe seeing what the CPU is doing in activity monitor might help us help you.
    – bmike
    Feb 28, 2021 at 17:57
  • @bmike There aren't any quantitative measurements. I just notice the lag especially when I'm typing (characters that I'm typing don't appear immediately). Feb 28, 2021 at 18:25
  • OK - I may try to answer the "how to install" question since that may be easily answerable and then you could ask a follow on question on how to diagnose keyboard lag on macOS Big Sur... As you see - just rolling back an OS is a long process if you need to cover all the bases and even longer if you don't use several KB that each are pretty detailed and have multiple steps.
    – bmike
    Feb 28, 2021 at 18:46
  • Can you check what the top CPU consumers are in /Applications/Utilities/Activity Monitor? (Make sure to switch to View -> All Processes and do a descending sort by CPU usage.)
    – pion
    Mar 1, 2021 at 7:56
  • @pion Yes, here it is imgur.com/a/HuRvtU1. I was exaggerating when I saw "it's VERY laggy." It is laggy. When I'm typing fast, the characters are noticeably lagging behind when I press the key. It was not doing this prior to the upgrade. Mar 1, 2021 at 20:47

2 Answers 2


Here is how I would back date a newer Big Sur system to 11.2.1

If you have a Time Machine Backup from before you ran the upgrade. That means you can erase the Mac - get the installer for 11.2.1 and then erase / install in a fairly straight-forward manner.

Once 11.2.1 is running, migrate data from the Time Machine snapshot or backup interval before the upgrade (or whatever your custom backup procedure entails). If you don't have a backup - make one now so you can hand migrate some of the easy apps and files that are compatible with a downgrade - some apps like Photos databases don't necessarily work backwards so you'd need to handle those errors and issues one by one.

Also - Catalina may have made a snapshot of your system that’s usable as a backup, so you would just boot to recovery and restore the system to that shapshot and not even need to worry about an installer.

And in macOS High Sierra or later, another snapshot is saved before installing any macOS update.

If you need to make a bootable 11.2.1 installer, here's how:

  1. Delete any Install macOS Big Sur apps you have in /Applications (or copy them to an external drive)
  2. Open terminal.app or another tool to get to the command line and issue this command

softwareupdate --fetch-full-installer --full-installer-version 11.2.1

Once the installer is there, follow this guide to make an installable USB for 11.2.1

Then follow this guide to erase install.

  • Unfortunately, I don't have a time machine backup. I actually just switched over to the 2019 macbook pro last week from my 2015 macbook pro, which was time machine backed up to my external HDD, but I don't have a USB-C cable for the HDD yet, so I haven't done any backups on the 2019 macbook. Mar 1, 2021 at 1:23
  • Not the end of the world @user5965026 - get one now while you sort out options. There’s no harm in getting a backup and then seeing if you can sort the slow and not have to roll back.
    – bmike
    Mar 1, 2021 at 2:59
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    Oh wait, I misread your post yesterday. The MacBook itself may also have a time machine backup (i.e., stored on the actual MacBook)? I wasn't aware that it could do that. That seems to be what the local snapshots link you linked me indicates. Mar 1, 2021 at 20:48

From your Activity Monitor screenshots, it looks like you're using Chrome. Chrome is notorious for excessive resource consumption on macOS. I would suggest switching to Safari and using it for a few days to see if your lag disappears.

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