TR RoboBench — Real-world transfers
RoboBench trades synthetic tests with random data for real-world transfers with a range of file types. Developed by our in-house coder, Bruno "morphine" Ferreira, this benchmark relies on the multi-threaded robocopy command build into Windows. We copy files to and from a wicked-fast RAM disk to measure read and write performance. We also cut the RAM disk out of the loop for a copy test that transfers the files to a different location on the SSD.
Robocopy uses eight threads by default, and we've also run it with a single thread. Our results are split between two file sets, whose vital statistics are detailed below. The compressibility percentage is based on the size of the file set after it's been crunched by 7-Zip.
|Number of files||Average file size||Total size||Compressibility|
The media set is made up of large movie files, high-bitrate MP3s, and 18-megapixel RAW and JPG images. There are only a few hundred files in total, and the data set isn't amenable to compression. The work set comprises loads of TR files, including documents, spreadsheets, and web-optimized images. It also includes a stack of programming-related files associated with our old Mozilla compiling test and the Visual Studio test on the next page. The average file size is measured in kilobytes rather than megabytes, and the files are mostly compressible.
RoboBench's write and copy tests run after the drives have been put into a simulated used state with 30 minutes of 4KB random writes. The pre-conditioning process is scripted, as is the rest of the test, ensuring that drives have the same amount of time to recover.
Read speeds are up first. Click the buttons below the graphs to switch between one and eight threads.
Although the P3700 continues to beat down its rivals, the XP941 is more competitive than one might expect, especially with the larger files in the media test. The M6e isn't nearly as fast at reading those files, but the gap narrows considerably in the work tests.
Even the mighty P3700 struggles to distance itself from the SATA field in the single-threaded work test. The read speeds in that test are low across the board, and upping the thread count delivers big gains. That said, the top speeds with eight threads are still well short of what the drives achieve with even a single thread in the media test.
RoboBench's write results paint a somewhat similar picture. Speeds are much higher in the media tests, and the PCIe pecking order is unchanged. However, the M6e gets nipped by a couple of SATA drives in the eight-thread media test, and it's near the bottom of the pile in the work tests.
This time around, the P3700 has a much greater advantage over the XP941 in the media tests. The Intel drive roughly doubles the write speeds of the Samsung regardless of the thread count. Its lead in the work tests remains slim, though.
As one might expect, the copy results look like a combination of the read and write scores. The P3700 maintains its lead over the XP941, which in turn trumps the M6e. The Plextor SSD is a smidgen faster than the SATA drives in three of four tests, but it's buried in the middle of the pack when copying work files with a single thread. To be fair, most of the drives are evenly matched there.
The old X25-M G2 struggles to keep up throughout RoboBench, and it's especially slow when dealing with the larger media files. The load-time tests on the next page show that the drive is still plenty quick for some tasks, though.