3 ms·

As the speed test was using a beta of High Sierra / APFS, I performed some tests of my own. I've written /dev/zero to the disk, and read Xcode_9_GM_seed.xip fro

by bouke 9y ago

As the speed test was using a beta of High Sierra / APFS, I performed some tests of my own. I've written /dev/zero to the disk, and read Xcode_9_GM_seed.xip from the disk using different block sizes using `dd`. I ran the read tests a few times, as there was a lot variation in the results. I've excluded the first result of the read results for each FS. The test was run on a Samsung Evo Pro 850 500GB SSD inside a Sharkoon USB-C case connected over USB-C to a MacBook Pro 2016 w/ Touchbar. Speed in MB/s HFS+ HFS+ Encrypted APFS APFS Encrypted 1M write 498 473 490 (-2%) 444 (-6%) 1M read 6896 6815 6860 (-1%) 6827 (0%) 4k write 486 477 485 (-0%) 445 (-7%) 4k read 2734 2709 2599 (-5%) 2545 (-6%) While there is still some performance degradation between HFS+ and APFS, it's within a single digit now.

stirner 9y ago
dd is not an acceptable benchmark. You need to eliminate the effects of buffering/caching to get accurate results.
- Someone1234 9y ago
  /dev/zero is also not an acceptable source of data; since \0\0\0\0\etc is unnaturally easy to compress. A large real file (e.g. installation ISO) may have been a better idea.
bouke 9y ago
Following the comments on the test method, I've run the 'Blackmagic Disk Speed Test'. The results are the following. Speed in MB/s HFS+ HFS+ Encrypted APFS APFS Encrypted read 513 513 508 506 write 477 460 478 432 The earlier results of 7 GB/s are quite impossible with the Samsung Evo Pro 850 -- those max out around 500 MB/s. So my earlier test results are invalid. The new test results mostly show that both file systems can saturate the disk's raw throughput. -- update On my internal Apple SSD (PCI-Express) I've created a partition for testing. I've kept "Blackmagic Disk Speed Test" running for a few minutes and took an average of the tests. The results are in favor of APFS, beating HFS+ by 3-17% in throughput. Speed in MB/s HFS+ HFS+ Encrypted APFS APFS Encrypted read 2400 2240 2700 (+13%) 2400 (+7%) write 1900 1930 2000 (+5%) 1980 (+3%)

by bouke 9y ago

stirner 9y ago

dd is not an acceptable benchmark. You need to eliminate the effects of buffering/caching to get accurate results.

Someone1234 9y ago
/dev/zero is also not an acceptable source of data; since \0\0\0\0\etc is unnaturally easy to compress. A large real file (e.g. installation ISO) may have been a better idea.

bouke 9y ago

Following the comments on the test method, I've run the 'Blackmagic Disk Speed Test'. The results are the following. Speed in MB/s HFS+ HFS+ Encrypted APFS APFS Encrypted read 513 513 508 506 write 477 460 478 432 The earlier results of 7 GB/s are quite impossible with the Samsung Evo Pro 850 -- those max out around 500 MB/s. So my earlier test results are invalid. The new test results mostly show that both file systems can saturate the disk's raw throughput. -- update On my internal Apple SSD (PCI-Express) I've created a partition for testing. I've kept "Blackmagic Disk Speed Test" running for a few minutes and took an average of the tests. The results are in favor of APFS, beating HFS+ by 3-17% in throughput. Speed in MB/s HFS+ HFS+ Encrypted APFS APFS Encrypted read 2400 2240 2700 (+13%) 2400 (+7%) write 1900 1930 2000 (+5%) 1980 (+3%)