AIDA64 Disk Benchmark
Many enthusiasts are familiar with the Finalwire AIDA64 benchmark suite, but very few are aware of the Disk Benchmark tool available inside the program. The AIDA64 Disk Benchmark performs linear read and write bandwidth tests on each drive, and can be configured to use file chunk sizes up to 1MB (which speeds up testing and minimizes jitter in the waveform). Because of the full sector-by-sector nature of linear testing, Benchmark Reviews endorses this method for testing SSD products, as detailed in our Solid State Drive Benchmark Performance Testing article. One of the advantages SSDs have over traditional spinning-platter hard disks is much more consistent bandwidth: hard disk bandwidth drops off as the capacity draws linear read/write speed down into the inner-portion of the disk platter. AIDA64 Disk Benchmark does not require a partition to be present for testing, so all of our benchmarks are completed prior to drive formatting.
Linear disk benchmarks are superior bandwidth speed tools because they scan from the first physical sector to the last. A side affect of many linear write-performance test tools is that the data is erased as it writes to every sector on the drive. Normally this isn’t an issue, but it has been shown that partition table alignment will occasionally play a role in overall SSD performance (HDDs don’t suffer this problem).
VX500-25SAT3-512G SSD Read Results
As shown above, average read performance was just under 510MB/s. This particular read result is one of the “smoothest” I’ve seen from a SATA SSD, with only 15MB/s separating the minimum speed from the maximum speed.
AIDA64 linear write-to tests were next…
512GB OCZ VX500 SSD Write Results
This chart was rather surprising: at just past 50% of the drive’s capacity, write performance falls into a hole, dropping to less than 100MB/s. Normally I’d attribute this to running off the edge of a cache, but I’m pretty sure the drive doesn’t have that much cache!
Now, remember that this test was run on a “clean” SSD. I thought it would be interesting to see what would happen if I ran the test again on a “dirty” drive, with block erasures required for almost every write:
It’s important to keep in mind that neither chart really reflects real-world conditions: the first test started with a “clean” SSD, so that all writes could proceed without any block erasures required. The second test results are with a completely “dirty” drive, with erasures required before virtually every write. In the “real world”, user results will be most similar to those in the first half of the first test, as the drive’s garbage collection routines and Windows TRIM will keep ample erased blocks available for most write operations.
The chart below shows the average linear read and write bandwidth speeds for a cross-section of storage devices tested with AIDA64. The Trion narrowly edges out of the VX500 in read speeds, although its more expensive stablemate wins on write speeds.
Linear tests are an important tool for comparing bandwidth speed between storage products, serve to highlight the consistent-bandwidth advantages of SSDs, which don’t suffer the read performance drop-off that HDDs do as the test proceeds away from the fast outer edge of the disk.
In the next section we use PCMark Vantage to test real-world performance…