Does BitLocker Slow Down Windows 10? Resolve BitLocker Performance Issue!

Many people store important data on their hard disks. You may use BitLocker to encrypt your data present on your hard disks. However many users suspect that using BitLocker often affects the read/write performance of the disk.

What Is BitLocker?

BitLocker is native disk encryption software provided by Microsoft on Windows 10 and below. It uses a lot of protectors to encrypt data so as to make the data accessible only to the authorized user. It is used primarily to protect important data and file security purposes.

If you move a test file between disks on a Windows 7 PC and then the same file on the same computer on Windows 10, you may notice a slight fall in the read-write performance of your SSD. You may think this might an issue with the OS, but as it turns out, it is not. BitLocker is slower on Windows 10 than on Windows 7.

Does BitLocker Slow Down SSD?

There is a short answer to this question. Yes, BitLocker slows down the performance of your SSD, but you need to understand why.

BitLocker Runs Slower On Windows 10

By default, BitLocker is made to run less aggressively on Windows 10 than Windows 7. It has been done to compensate for the background encryption conversion mechanism that BitLocker now follows.

According to this new conversion mechanism, once you lock a drive, any new writes to the disk are always encrypted regardless where they land on the disk. It immediately guarantees the encryption of these new writes immediately after BitLocker is enabled on the PC.

Advantages Of This New Encryption Mechanism

Earlier with the older encryption method, users had to wait for the entire disk to reach the 100% process mark before placing any new files on the SSD. Without the drive fully encrypted, there was no way of guaranteeing that your data wasn’t already compromised.

With the new encryption mechanism, users can safely copy sensitive data to the disk as soon as BitLocker is enabled and the volume is being encrypted in the background.

What Does This Mean?

This new mechanism results in slower initial encryption. Users will notice a significant increase in the time taken for complete encryption in Windows 10 than Windows 7.

A slower BitLocker means, however, a faster foreground resource use. The user will feel the system to be not impacted at all by the BitLocker process running in the background.

BitLocker May Not Encrypt Your SSD At All

When available, hardware-based encryption is faster than software encryption (like BitLocker). If the SSD you are using says that it can handle hardware encryption, BitLocker trusts your SSD to handle the encryption, and it does nothing at all.

This happens because relying on the hardware-based encryption can result in improved performance of your system.  However many SSD manufacturers cannot be trusted to implement the best encryption hardware, and if they have made this false claim, turning on BitLocker may not encrypt the data at all, leaving your device in a vulnerable state.

How To Make SSDs Use BitLocker By Default?

You can make sure that your data is encrypted using BitLocker’s software-based encryption. However, keep in mind that BitLocker is slower Windows 10 than Windows 7 as stated above.

You need to make changes to the Local Group Policy Editor to always use BitLocker. Use the following steps to do so:

1. Open Group Policy Editor by pressing Win + R to launch Run and typing msc and press Enter.
2. Navigate the following path:

      3. From the right pane, double click on “Configure use of hardware-based encryption for fixed data drives” to modify the value.

      4. Click on the Disable radio button to disable the hardware-based encryption on SSDs.

  5. Un-encrypt and re-encrypt your drive afterward for this change to take effect.

Conclusion

It is difficult to answer a question like Does BitLocker slow down SSD as there are many factors affecting the same. But I think now you may have a clearer idea as to why the small performance loss occurs on a Windows 10 running an SSD. Comment down below if you found this helpful or have any other queries.