High RAM pressure after update, how does macOS handle purgeable/compressed memory, and is there a safe way to free it?

15.7.1 is the current release of Sequoia. You should update from your 15.0.x versions. There have been a lot of fixes since 15.0 came out.

IMHO you also have too much running simultaneously on your 8GB MBAir and perhaps even on your 16GB MBAir. It's also no surprise that an 8GB MBAir is feeling memory pressure ... Apple upped all base Macs to 16GB about a year ago, I suspect in acknowledgement that 8GB was insufficient for current releases of macOS & apps.

It would be useful to know the capacities of the internal SSDs and how much free space is on each. If they are nearing capacity all sorts of gremlins may appear.

Two cents here and just to add to what my colleague @den:thed has already suggested

Use the Activity Monitor application and select View >> View All Processes.

Identify the processes using the most CPU and memory.

Often, it’s a combination of processes.

When the computer uses a lot of CPU and Memory, it may indicate a lack of empty space on the drive.

In this case, the CPU and Memory usage increase as the system searches for empty space to save changes.

Also, consider the number of Web Browser tabs in use. Each tab may consume significant CPU and Memory resources.

View memory usage in Activity Monitor on Mac - Apple Support

Aliyaarafridi wrote:

Hi folks,

I’m on MacBook Air [M1/M2], [8/16] GB RAM, macOS [version e.g., 15.0.x/Sequoia]. Since updating, RAM pressure stays yellow/occasionally red even when I close apps. Activity Monitor shows Purgeable and Compressedmemory growing while Free remains low.

Repro steps (typical):1.

Boot fresh → open Safari (10–15 tabs), Notes, Mail.

2. After ~30–60 mins, memory pressure climbs; Swap Used rises to [value] MB.

3. Quitting apps doesn’t immediately drop pressure; system feels stuttery (Mission Control animations lag).

What I’ve tried:•

Restart, Safe Mode, new test user.

• vm_stat and memory_pressure CLI checks.

• Disabled login items/background agents.

• No third-party cleaners installed.

Questions:

Is this expected1.  with macOS memory compression/purgeable caches?

Any Apple-recommended1.  way to nudge the system to reclaim purgeable memory (CLI or otherwise)?

Best practice to diagnose a leaky app1.  (sample processes, spin reports, logs)?

I am unclear how much RAM is on the logicboard...

Not sure how I am suppose to interpret <MacBook Air [M1/M2], [8/16] GB RAM> ?

8 GB of RAM hardly cuts it today, so it is considered the barest minimum.

The adage is unused RAM is wasted RAM— so you would hope it is taking advantage of the total.

Swap file in MB is nothing....it takes 1000MB is equal to 1 GB

You should not have to micro-manage RAM in a contemporary macOS.

unplug all non-essential peripherals when testing

Uninstall all third party apps that are Cleaners/Optimizers/VPN/Anti-Virus

all known to cause issues on the macOS

To trouble shoot further you can:

—A SafeBoot Start up your Mac in safe mode - Apple Support will sort many anomalies

Does a quick disk repair before it fully boots up, and certain system caches get cleared and rebuilt, third party system modifications and system accelerations are disabled temporarily.

Login and test. Reboot as normal and test. Caches get rebuilt automatically.

This test will tell you if third party interference; most extensions etc are not loaded in safe boot mode.

—Test issue in another user (or guest user) account Change Users & Groups settings on Mac - Apple Support

This will tell you if it a universal issue or isolated to your user/admin account. 

***wireless keyboard with rechargeable batteries— connect the charging cable, this will make the wired keyboard successful Safe Boot your Mac.

no insight or resolve—

You can get a good look at your User/System config. and reveal conflicts or issues, you can download/run this trusted utility https://etrecheck.com

If you need help interpreting the report you can post it here in its entirety in the "Additional Text" box in the editing toolbar below, in your reply.

How to use the Add Text Feature when posting an Etrecheck Report—OldToad

How to use the Add Text Feature When Post… - Apple Community

1) macOS has it own way of handling and automatically allocating Memory.

Reducing your app’s memory use | Apple Developer Documentation

View memory usage in Activity Monitor on Mac - Apple Support

2) macOS has all of the Security built into the system.

Apple Platform Security - Apple Support

Ditch the third-party Memory utility and any other Anti Virus, Protecting, Cleaning App's that you have installed on that Mac. Those third-party junk-ware utilities and app's do nothing except, bog down, use unnecessary (CPU & Memory) resource and in some cases can send your Mac of the cliff.