Why SSDs Slow Down When They’re Full

Solid-state drives (SSDs) are storage devices that have replaced hard drives in most laptops and computers nowadays. Their main advantages are the lack of mechanical parts and increased speed. However, SSDs can slow down when they get full. This article explores why this happens and what you can do about it.

Understanding Why SSDs Slow Down

To understand why SSDs slow down when they get full, you need to know how they work.

SSDs are made of small units called blocks, which store information when data is written to them. The more data you store, the fewer empty blocks are available. An almost full SSD typically doesn’t have any empty blocks, only partially filled ones.

When you try to write a file to a nearly full SSD, the device cannot use partially empty blocks directly. It must first move the existing content into the cache and then modify it with the new data before writing it back to the block. This process takes considerable time, especially when writing multiple files, causing the SSD to slow down noticeably. Allowing your SSD to have empty blocks can avoid these issues.

What to Do When Your SSD Slows Down

When you notice your device slowing down, you should check the capacity of your SSD to see if it’s full. Here’s how to check the capacity:

On Windows

1. Open File Explorer:
   • Go to This PC.
   • Look under Devices and drives to see the status bar showing the available space on your SSD.

On Mac

1. Go to the Apple Menu:
   • Select About This Mac.
   • Click on More Info.
   • Scroll down to find Storage and select Storage Settings to see the available space on your SSD.

If your SSD is almost full, try these methods to free up space:

Empty the Recycling Bin

1. Right-click on the Bin icon.
2. Select Empty Bin or Empty Recycling Bin.

Delete Hidden Files

1. Open Control Panel using the search bar.
2. Find File Explorer Options.
3. Go to the View tab.
4. Check the box next to Show hidden files, folders, and drives.
5. Delete unnecessary hidden files.

Uninstall Programs

On Windows

1. Type Apps and features in the search bar.
2. Find unnecessary apps.
3. Click Uninstall to delete them.

On Mac

1. Open Launchpad.
2. Search for the app you want to delete.
3. Press and hold the Option key until the apps start to shake.
4. Tap the cross button on the corner of the app.
5. Select Delete to confirm.

Replace Your SSD

If your SSD is still slow after trying these methods and there’s nothing left to remove, you may need to replace it with a higher-capacity one. Upgrading your SSD can improve performance significantly.

How to Avoid SSDs Slowing Down

To prevent your SSD from slowing down, avoid filling it to capacity. Regularly check its capacity and delete unnecessary files and programs. Empty your recycling bin periodically, and uninstall programs you no longer need.

Should You Leave Some Space on Your SSD?

Yes, you should leave some space on your SSD to maintain its performance. Although SSDs generally perform better than hard drives, a full SSD can still slow down.

How Much Free Space Should I Leave on My SSD?

It’s generally recommended to leave about 20-30% of your SSD’s capacity free. This helps ensure optimal performance. Some SSDs use overprovisioning, reserving a portion of the drive that is not accessible to the user to help maintain performance. Despite overprovisioning, leaving around 20% of your SSD empty is a good practice to avoid slowdowns.