NAS cpu performance

Network attached storage units (NAS units) are increasingly popular as the needs for storage increase and more and more people don't keep a traditional desktop computer with room for multiple disk drives for storage.

Traditional NAS benchmarks often focus on file transfer over network which indeed is the core use case for most. But when desktop usage is declining more and more tasks are shifted to NAS devices and this means new capabilities are needed, running virtual machines and media playback is no longer exotic or a niche.

NAS benchmarks needs to evolve to give relevant guidance to buyers for these new scenarios, network transfer performance is no longer enough to make a decision. This need is emphasized by the huge difference in performance between different devices, for devices sometimes at similar price.

A very basic test can be run on almost any linux based NAS unit. It doesn't nearly give complete information but it can give a very rough estimate of single thread CPU performance, it's not a good complete benchmark, but it's better than nothing:

time $(i=0; while (( i < 999999 )); do (( i ++ )); done)

Results for a few Synology devices (lower time is better):

DS115J	68s
DS212	67s
DS213	59s
DS214+	42s
DS412+	22s
DS413J	67s
DS414	40s
DS415+	14s
DS416play	12s
DS718+	7.7s
DS916+	11s
DS918+	7.8s
DS1512+	22s
DS1812+	21s
DS1815+	13s
DS3018xs	4.1s
RS3617RPxs	3.5s

As the results show, devices have vastly different CPU capabilities despite all of them capable of transferring files at very high speed.