Bought this drive as a dedicated Time Machine backup drive for an M1 MacBook (OS 11.5.2). Specific model to avoid is WDBPKJ0050 and this appears in your USB device tree as 'WD My Passport 2627'.
My assessment is that in any case, this drive is unsuitable for any long-running write, and is in particular, bad for backups. That's a reliability as well as a performance problem. It's possible that WD used a very low-quality platter and attempted to improve short-term performance with a buffer.
When swapped in as a replacement to increase capacity, we were surprised how slowly a standard Time Machine backup progressed, and investigated with some large-file write benchmarking.Įven when connected to a dedicated USB3.1 bus, my basic tests to the unit I bought, of a linear large-file write, showed that it can barely take 40MB/sec for a few seconds at the start of continuous writes, and then quickly degrades to 9MB/sec or worse sometimes it stalls completely and write performance drops to nil.īy comparison, I have several comparable 5TB portable-backup drives from other manufacturers, and even other similar drives from WD, and these consistently sustain writes of 100MB/sec, using the same port and cable and test method. This drive cannot sustain high speed writes.
