Btrfs RAID Benchmarks With The Linux 4.4 Kernel On Samsung 850 SSDs
The latest Linux disk testing fun at Phoronix has been stressing two Samsung 850 EVO solid-state drives on the Linux 4.4 kernel when using the native RAID capabilities built into the Btrfs file-system.
As it's been a while since last running any Btrfs RAID SSD benchmarks on Phoronix, with the Linux 4.4-rc2 kernel I tested the latest RAID0 and RAID1 performance on two Samsung 850 EVO SSDs. The RAID0 and RAID1 performance with the two SSDs was also compared to the standalone Btrfs file-system performance on a single SSD. Additionally, when in the RAID1 mode I also did a few extra runs when testing various Btrfs mount options.
The extra RAID1 mount option tests were running this two-disk array with LZO compression enabled, LZO compression enabled and setting nobarrier, and lastly was LZO + Nobarrier + Noatime. These extra runs are basically for reference purposes in looking at ways to potentially improve the Btrfs RAID1 performance while safeguarding your data but being more competitive. Of course, nobarrier wouldn't be recommended unless you have a back-up battery source for the system. Using Noatime could also be problematic for certain applications/workloads. Lastly, while LZO compression can be great, in some of these synthetic benchmarks the compression results can be portrayed as too great due to the sample data being easily compressed. Again, this article is mainly being done for reference purposes.
If you are unfamiliar with setting up Btrfs RAID on multiple devices, see the Btrfs Wiki for all of the details.
All of these Btrfs RAID benchmarks from the Linux 4.4 kernel can be found on the pages ahead. All tests were automated in a fully reproducible manner using the open-source Phoronix Test Suite.