---
title: "Find out why your Mac is slow · MacMelon"
description: "A slow Mac is usually short on memory, not old. Check memory pressure and swap, see what holds memory, and fix it with Sentinely after you review the change."
url: "https://macmelon.com/use-cases/find-out-why-your-mac-is-slow"
---

# Find out why your Mac is slow

Beachballs and laggy app switches usually mean memory pressure and swap, not an old Mac. Run the free check and read what is actually holding memory.

When a Mac feels slow, the processor is rarely the problem. More often, the apps you have open need more memory than the Mac has. macOS compresses what it can, then writes the rest to disk as [swap](https://macmelon.com/glossary/swap-memory). Switching back to an app means waiting for its memory to come back. That is the pause you feel.

[Sentinely](https://macmelon.com/apps/sentinely) reads [memory pressure](https://macmelon.com/glossary/memory-pressure), swap, and what each app is holding, and tells you in plain language whether anything is wasting memory. If nothing is, it says so. The cluster guide is [How to find what's slowing down your Mac](https://macmelon.com/guides/how-to-find-what-is-slowing-down-your-mac).

## Steps

1.  ### Run the free check

    Open Sentinely. It takes a few seconds to read memory pressure, swap, and the memory footprint of what is running. The check is free.

2.  ### Read the diagnosis

    Findings are ranked by how much memory they hold. Each one names the app or helper, says why it is holding memory, and gives an estimate. For apps made of many processes, the estimate is marked "up to", because those processes share some memory.

3.  ### Review a fix

    Pick a finding. Sentinely shows which processes it will ask to quit and re-checks them just before acting. Your first fix is free.

4.  ### Read the receipt

    Sentinely measures ten seconds after the fix and again at one minute. Freed is the memory that came back. Felt is what changed in memory pressure and swap. If nothing improved, the receipt says so.

## Before you start

-   Memory is not the only reason a Mac slows down. A nearly full disk, heat, or one process stuck at full CPU can do it too. If your disk is the problem, use [Disk Housekeeper](https://macmelon.com/apps/disk-housekeeper).
-   A large swap file on its own is not a problem. It matters when the Mac keeps reading memory back from it, which is what Sentinely's receipt measures.

## Questions

Is my Mac too old?

Often not. An older Mac with less memory reaches memory pressure sooner, but the cause is usually what is running on it. The check shows whether that is the case before you think about new hardware.

Will Sentinely tell me to restart?

Only when memory pressure stays high after everything it can fix has been handled and swap is still very large. Never because of how long the Mac has been on.

## Apps

[No more Force Quit in the middle of a build. ### Sentinely](https://macmelon.com/apps/sentinely)

## Related guides

[### How to find what's slowing down your Mac](https://macmelon.com/guides/how-to-find-what-is-slowing-down-your-mac)

## Related use cases

[### When Slack, Teams, or Discord slows your Mac](https://macmelon.com/use-cases/slack-teams-and-discord-slowing-your-mac)[### Stop AI-tool helpers left running after you close your editor](https://macmelon.com/use-cases/stop-leftover-ai-helpers-and-mcp-servers)[### Free up space on a MacBook](https://macmelon.com/use-cases/free-up-space-on-a-macbook)

## Related terms

[How hard macOS is working to make room in memory. The signal that a Mac is actually short on memory, not just using it. ### Memory pressure](https://macmelon.com/glossary/memory-pressure)[Memory macOS has moved from RAM to the startup disk because RAM ran short. ### Swap](https://macmelon.com/glossary/swap-memory)[Memory macOS has squeezed in place to make room, before it writes anything to disk. ### Compressed memory](https://macmelon.com/glossary/compressed-memory)[The memory macOS charges to a process, including memory it has compressed. Sentinely's unit for estimates and receipts. ### Memory footprint](https://macmelon.com/glossary/memory-footprint)[Sentinely's record of a fix: what was freed and what changed for you, measured after the fix rather than promised before it. ### Measured receipt](https://macmelon.com/glossary/measured-receipt)

## Related notes

[Empty memory is not the goal, and a number we cannot measure is not a result. The rules behind Sentinely's fixes and its measured receipts. ### Why Sentinely won't "free your RAM"](https://macmelon.com/blog/why-sentinely-wont-free-your-ram)