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Comparison Products
We tested the Extreme Pro v2 against its predecessor, the Extreme Pro v1, as well as a few of the best portable SSDs available. We threw in Samsung’s X5, LaCie’s Rugged SSD Pro, and Sabrent’s Rocket XTRM-Q 8TB as high-end Thunderbolt 3 alternatives, as well as a WD Black P50, another USB 20 Gbps contender. We also added the LaCie Rugged SSD, Samsung T7, and Crucial X8 as cheaper 10Gbps competitors.
Transfer Rates – DiskBench
DiskBench is a storage benchmarking tool that allows us to test the transfer or copy performance of a storage device with real data. We test external drives with three file transfers that consist of 25GB of photos (10GB of .jpg and 15GB of .RAW photos), 50GB of movies, and 25GB of documents. First, we transfer each folder from a 1TB NVMe SSD to the external device; then, we follow up by reading a 3.7GB 7-zip file and a 15GB movie back from the device.
SanDisk’s Extreme Pro v2 delivers exceptional file copy and read performance. While the Thunderbolt 3 SSDs outperformed the Extreme Pro and the WD Black P50 in the large file transfer tests, they were outperformed during the 25GB documents transfer because the workload taxes them with writing small random files.
Trace Testing – PCMark 10 Storage Test: Data Drive Benchmark
PCMark 10 is a trace-based benchmark that uses a wide-ranging set of real-world traces from popular applications and common tasks to measure the performance of storage devices. To test drives that store files rather than applications, we utilize the Data Drive Benchmark.
Scoring fourth place in PCMark 10’s data drive storage benchmark, SanDisk’s Extreme Pro v2 again delivers exceptional responsiveness for a portable SSD. We noted a remarkable improvement over its predecessor. The v2 is nearly on par with the Samsung X5, which easily surpassed the performance of its 10 Gbps competition.
Synthetic Testing - ATTO / iometer
iometer is an advanced and highly configurable storage benchmarking tool, while ATTO is a simple and free application that SSD vendors commonly use to assign sequential performance specifications to their products. Both of these tools give us insight into how the device handles different file sizes.
SanDisk’s Extreme Pro v2 displays very strong sequential read and write performance with notable gains at smaller file sizes compared to the older WD Black SN750-powered WD Black P50. The NVMe protocol aids the Thunderbolt 3 SSDs, so they tend to respond much faster across the board.
Sustained Write Performance, Cache Recovery, and Temperature
Write speed and temperature are two important and inter-related metrics for external devices. Official write specifications are only part of the performance picture. Most SSDs implement a write cache, which is a fast area of (usually) pseudo-SLC programmed flash that absorbs incoming data. Sustained write speeds can suffer tremendously once the workload spills outside of the cache and into the "native" TLC or QLC flash. We use iometer to hammer the SSD with sequential writes for 15 minutes to measure both the size of the write cache and performance after the cache is saturated. We also monitor cache recovery via multiple idle rounds.
We also monitor the temperature of the drive via the S.M.A.R.T. data and an IR thermometer to see when (or if) thermal throttling kicks in and how it impacts performance. Bear in mind that results will vary based on the workload and ambient air temperature.
Second only to the super-expensive 8TB Sabrent Rocket XTRM-Q, SanDisk’s new 2TB Extreme Pro v2 boasts impressive write performance. The SSD wrote 32GB of data at a rate of roughly 2 GBps before degrading to a consistent direct-to-TLC performance of 1.6 GBps. After 30 seconds of idle time, the SanDisk Extreme Pro reclaimed the full capacity of its static SLC write cache.
SanDisk’s Extreme Pro v2 idles a little warm, with the surface of the device measuring 40 degrees Celsius when simply connected to the system, or roughly 6-10 degrees Celsius hotter than most 10Gbps devices. (The S.M.A.R.T. data reports a device temperature of 44 degrees Celsius.)
The performance never slowed due to throttling, even after writing 600GB of data to the devices. While the drive runs warm, it will deliver exceptional performance most of the time thanks to the chassis acting as a heatsink. Maximum temperatures hit roughly 48 degrees Celsius on the surface (S.M.A.R.T. data reported 58 degrees Celsius.)
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