Unsung Heroes: 14 Years of Hard Drive Performance

Our PCMark Vantage results were interesting to say the least. Between 1996 and 2000, hard drive performance nearly tripled—then shot up again when WD introduced the 800JB series of drives with 8MB of on-board cache. The 36GB Raptor made mincemeat out of Seagate's 7200.7 hard drive, but was trounced by the 7200.10, which beats out even a pair of 36GB Raptors in RAID 0. The Caviar Black 1TB  and 2TB drives essentially tie, while the WD Velociraptor proved faster than even the dual-processor, 64MB cache version of the Caviar Black. In 14 years hard drive performance has increased eleven-fold.  To quote someone famous, or infamous... verrrry niiice.


Our synthetic tests of HDD read/write performance show significant improvement over time, albeit not to the same degree as in PCMark Vantage. Its 8MB of cache doesn't help the WD800JB compared to its 2MB brother, while Seagate's 7200.10 HDD again overtakes WD's Raptor. The single VelociRaptor is still the fastest drive in the house, but the two 36GB Raptors are right on its tail.


We're betting that the Raptor's stronger showing here is because Read/Write tests are relatively simple with light/no concurrent request load. Western Digital's first generation of Raptors were IDE drives with a SATA bridge chip and lacked NCQ support.

Finally, there's access latency.

Access latencies dropped significantly around the time the WD800JB was introduced but have remained relatively close to each other ever since. The exception to this rule is Western Digital's VelociRaptor series, which spin at 10,000 RPM instead of 7200 and perform commensurately better. Access latencies are the Achilles heel of hard drives; this is one area where a mechanical drive will never be able to match an SSD's performance. Despite this, the hard drive improvements are impressive in their own right.

High-end SSDs now offer performance that hard drives can't match, but legacy desktop hard drive performance scaled much better than we initially thought it would. In all the excitement over SSDs, it's easy to forget that flash-based products face an uncertain future. As process geometries scale ever smaller, transistor leakage and soft error rates become a real issue. This is an issue that will have to be solved in order for SSDs to compare more favorably the hard drives in terms of $/GB.

After examining 14 years of data we've got to admit that hard drives have gotten a bit of a bum rap. Granted, they're still the slowest part of the system, but HDD manufacturers deserve a bit more credit than they typically get. Anyone who doesn't think so is welcome to borrow the Caviar 2GB we tested—a few days with it, and you'll be singing a different tune.