FIX · MEMORY
Memory Compression using a lot of RAM: normal, or a problem?
Memory Compression is not an app and has no file to scan. It is where Windows keeps memory it has squeezed instead of writing it to disk. When it grows, it is usually a sign that something else needs the RAM, so the entry worth looking at is often the one above it in Task Manager.
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TECHNICAL SUMMARY
| What it is | The store of compressed pages in RAM |
|---|---|
| Why it grows | Memory pressure: Windows compresses instead of paging |
| File on disk | None shown: Get-Process lists no path for it |
| Turn it off | Disable-MMAgent -mc, as administrator (not recommended) |
| PC Tweaker plan | No control for it |
What it does
Microsoft introduced the compression store in Windows 10 as an in-memory collection of compressed pages. When the Memory Manager feels memory pressure, it compresses unused pages instead of writing them to disk. That keeps more applications in physical memory at a time, and Microsoft says it helps responsiveness. Reading a compressed page back from RAM avoids going to the page file for it.
Why the number looks alarming
Microsoft's point is worth keeping in mind: the store's memory grows exactly when memory is being made available to other processes. Windows 10 kept the store in the System process, which is why System looked larger than in earlier releases. On current Windows 11 it has its own entry: on our test PC (build 26300) Get-Process lists Memory Compression with no file path and a working set of 239 MB at the moment we looked. A large figure means Windows had a lot to compress. It does not mean those gigabytes are wasted.
When to look closer
Compression is doing its job when the PC stays responsive. Look further if memory is nearly full all the time, if the disk is busy while you are doing little, or if one program keeps growing until you restart it. Sort by memory to find which one, then update, restart or replace it. If you regularly run out of memory with normal work, more RAM is the fix that no setting can replace.
Should you turn it off?
Windows gives you a command for it, but we do not recommend using it on a normal PC. With compression off, Windows has lost the alternative Microsoft describes to writing those pages to disk, and that does not create any extra memory. Microsoft's cmdlet page does not say whether a restart is needed, so restart before you judge the result.
Do it by hand
See its size (read-only)
PowerShellGet-Process -Name "Memory Compression" | Select-Object Id, @{n='MB';e={[math]::Round($_.WS/1MB)}}See what is really using memory (read-only)
PowerShellGet-Process | Sort-Object WS -Descending | Select-Object -First 10 Name, @{n='MB';e={[math]::Round($_.WS/1MB)}}Check whether compression is on (as administrator)
Look at the MemoryCompression line. In a window that is not elevated, this returned Access denied on our test PC.
PowerShellGet-MMAgentTurn it off (as administrator)
PowerShellDisable-MMAgent -mcTurn it back on (as administrator)
PowerShellEnable-MMAgent -mc
With PC Tweaker
PC Tweaker has no control that turns memory compression on or off. Its Smart RAM booster does a different job: it releases Windows' standby memory cache when free memory drops below your threshold, and it does not change compression.
Rather not edit the registry by hand?
PC Tweaker shows the exact change before it runs, records the value it replaces and puts it back with Restore. The Free plan needs no account. If a payment fails or a plan ends, Pro tools lock; changes already applied stay as they are and Restore still undoes them.
Common questions
What is Memory Compression in Task Manager?
It is the store of compressed pages in RAM. Under memory pressure, Windows compresses unused pages instead of writing them to disk.
Why is Memory Compression using so much RAM?
It grows when Windows has a lot to compress, which usually means other programs need the memory. Sort Task Manager by memory to see which ones.
Should I disable Memory Compression?
We do not recommend it on a normal PC. It does not create extra memory, and it removes the alternative to writing those pages to disk. Disable-MMAgent -mc turns it off and Enable-MMAgent -mc turns it back on, as administrator.
Is Memory Compression a virus?
No program file is behind this entry: on our test PC Get-Process lists it with no path. It is part of how Windows manages memory.
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