iXsystems TrueNAS R-Series (ISCSI)

Model number: TrueNAS R20
Storage Category: Software Defined Storage - Hybrid
Drive quantity, size, type:

• 10 x 10TB SAS HDD HUH721010AL4200
• 1 x 3.84TB SAS SSD XS3840SE70055 (Read cache)
• 1 x 960GB SAS SSD XS960SE70055 (Write cache)

Storage configuration: 5x ZFS mirrors, 1x ZFS L2ARC read cache, 1x ZFS SLOG write cache device
Firmware version: 23.10.0
Connection protocol and speed: 10 GbE iSCSI
Additional support: All models and configurations of TrueNAS R-Series R20 with specifications equivalent or greater than the above

General product family overview:
TrueNAS is an Open Source storage operating system built on OpenZFS. With the TrueNAS R-Series, iXsystems integrates TrueNAS with the single-controller hardware that has configurable performance.
The TrueNAS R20 single controller hardware is a compact 2U system with 12 drives.

Vendor Settings:

• Caching used: Yes
• Read/write caching: Secondary ARC device acts as a read cache. ZFS uses ARC to cache recently and frequently accessed data. As new data is added to primary ARC the older data is moved to secondary ARC, which can be accessed faster than data off of the HDD array. In this test the 960GB SAS SSD was used as secondary ARC. ZFS SLOG is used for synchronous writes. Data is first written to RAM, then to the SLOG device, and then moved to the HDD array. For synchronous writes this allows the file system to confirm that data is written to non-volatile storage far faster than HDD allows. This test used the 3.84TB SAS SSD as SLOG, overprovisioned to 16GB.
• Networking: MTU=9000
• Multipathing / link aggregation used: No
• Array deduplication used in testing: No
• Array compression used in testing: Yes