Hi. I can't find definitive answer to this - does turning on File Vault slow down an M1 Mac when using it for video editing in FCP? On older Macs it was a bad idea to use File Vault and I know in theory it should be fine on newer Macs as the encryption is done on the T2 chip, but can anyone comment on real world experience? Thanks.
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File Vault, M1 & FCP - affect performance?
- Thread starter ianhhh123
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On M1 Macs(and T2 Macs), your data partition is encrypted even with File Vault turned off. Turning File Vault on does not re-encrypt the volume, but it protects the key to decrypt the volume using your password. Therefore File Vault does not affect storage performance at all.
Depends maybe on your definition of “older” Macs. Never had noticeable impact from using File Vault on any Macs.
There is a noticeable impact on I/O performance on Macs without T2 chips. My iMacs SSD performance decreased from 950/900 MB/s read/write to 650/600 MB/s read/write with FileVault enabled. The question is whether this decrease will have any impact on day-to-day performance and, most importantly, subjective performance. I am not a video editor but I can see how decreased I/O performance can have a major impact on real-world performance when importing, exporting, or scrubbing through a video.
As @Gnattu has already stated Macs with T2 chip are not subjected to this performance hit because their SSDs are encrypted by default, and enabling FileVault will simply protect the encryption key with a separate password. That's why disabling/enabling FileFault on T2 Macs is instantaneous whereas it can take several days to fully decrypt/encrypt a hard drive or SSD on a non-T2 Mac.
You are welcome of course to your view and I appreciate the helpful explanation. But I disagree. For me there is no NOTICEABLE impact even on Macs without T2 chips. This is clearly down to individual perception, usage and Mac specification. I base my view on normal usage and not performance tests.
I don't think we're that far apart in our assessment and opinion. What we can most certainly agree on is that encrypting a storage device on Macs without T2 chip does have an impact on I/O performance that is easily measurable and most importantly reliably reproducable. However, the effect on real-world everyday performance will be negligible in most cases except those that rely heavily on aforementioned I/O performance, such as for example handling large files. Hence you are absolutely correct in that for most users there will be no noticeable impact even on Macs without T2 chip.
Most importantly though this is a moot point. Op is asking about the impact of FileVault drive encryption on M1 Macs, and in this specific case the effect is not only negligible but completely non-existent.