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Performance cost of dm-crypt (LUKS) with btrfs on SSD

I just finally managed to encrypt my home folder and I wanted to check what is the performance cost of the encryption. It was great to see that none (doing simple synthetic benchmarking)!

Benchmarking

I followed Arch Linux benchmarking wiki and used dd for the benchmark. As you can see on the numbers bellow, they are practically same.

Encrypted disk

[root@think460s ssd_encryption]# dd if=/dev/zero of=tempfile bs=1M count=1024 conv=fdatasync,notrunc status=progress
1024+0 records in  
1024+0 records out  
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 1.38944 s, 773 MB/s  
[root@think460s ssd_encryption]# echo 3 > /proc/sys/vm/drop_caches
[root@think460s ssd_encryption]# dd if=tempfile of=/dev/null bs=1M count=1024 status=progress
993001472 bytes (993 MB, 947 MiB) copied, 2 s, 496 MB/s  
1024+0 records in  
1024+0 records out  
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 2.14522 s, 501 MB/s  
[root@think460s ssd_encryption]# dd if=tempfile of=/dev/null bs=1M count=1024 status=progress
1024+0 records in  
1024+0 records out  
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 0.312154 s, 3.4 GB/s  
[root@think460s ssd_encryption]# dd if=tempfile of=/dev/null bs=1M count=1024 status=progress
1024+0 records in  
1024+0 records out  
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 0.225289 s, 4.8 GB/s  
[root@think460s ssd_encryption]# dd if=tempfile of=/dev/null bs=1M count=1024 status=progress
1024+0 records in  
1024+0 records out  
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 0.2137 s, 5.0 GB/s  
[root@think460s ssd_encryption]# dd if=tempfile of=/dev/null bs=1M count=1024 status=progress
1024+0 records in  
1024+0 records out  
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 0.231491 s, 4.6 GB/s  
[root@think460s ssd_encryption]# dd if=tempfile of=/dev/null bs=1M count=1024 status=progress
1024+0 records in  
1024+0 records out  
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 0.241452 s, 4.4 GB/s

On non-encrypted disk

[root@think460s ~]# dd if=/dev/zero of=tempfile bs=1M count=1024 conv=fdatasync,notrunc status=progress
1024+0 records in  
1024+0 records out  
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 1.50617 s, 713 MB/s  
[root@think460s ~]# echo 3 > /proc/sys/vm/drop_caches
[root@think460s ~]# dd if=tempfile of=/dev/null bs=1M count=1024 status=progress 
1001390080 bytes (1.0 GB, 955 MiB) copied, 2 s, 500 MB/s  
1024+0 records in  
1024+0 records out  
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 2.12489 s, 505 MB/s  
[root@think460s ~]# dd if=tempfile of=/dev/null bs=1M count=1024 status=progress 
1024+0 records in  
1024+0 records out  
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 0.299011 s, 3.6 GB/s  
[root@think460s ~]# dd if=tempfile of=/dev/null bs=1M count=1024 status=progress 
1024+0 records in  
1024+0 records out  
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 0.223807 s, 4.8 GB/s  
[root@think460s ~]# dd if=tempfile of=/dev/null bs=1M count=1024 status=progress 
1024+0 records in  
1024+0 records out  
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 0.217937 s, 4.9 GB/s  
[root@think460s ~]# dd if=tempfile of=/dev/null bs=1M count=1024 status=progress 
1024+0 records in  
1024+0 records out  
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 0.220103 s, 4.9 GB/s  
[root@think460s ~]# dd if=tempfile of=/dev/null bs=1M count=1024 status=progress 
1024+0 records in  
1024+0 records out  
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 0.216287 s, 5.0 GB/s

Configuration

  • drive: SanDisk SD8TN8U512G1001
  • CPU: i7-6600U
  • Arch Linux: 4.17.13-arch1-1-ARCH

cryptsetup status

sudo cryptsetup status home-dan-encr                                                              22:04:01  
[sudo] password for dan: 
/dev/mapper/home-dan-encr is active and is in use.
  type:    LUKS2
  cipher:  aes-xts-plain64
  keysize: 256 bits
  key location: keyring
  device:  /dev/sda6
  sector size:  512
  offset:  8192 sectors
  size:    660594688 sectors
  mode:    read/write