The latest WD Raptor, the WD740ADFD, is the fastest commercially available SATA Hard Disk at present (January 2007). And the Areca 1231ML and other 1280 series RAID cards (no sure what happend to their series numbering there) being full Hardware RAID, and using the Intel IO341 chip, are generally acknowledged to be the fastest or thereabouts of the server RAID cards. So the best the mankind can achieve in performance (given an acceptable level of data security) with hard disks is represented by around 10 of the latest WD Raptors in RAID6. We will compare HyperDrives against 8 Raptors in RAID0 which will be around 10-20% faster than 10 Raptors in RAID6.
Furthermore, with Hard Disks, the more you use, the more likely you are to have a mechanical failure. So the maintenance cost of very large arrays of Hard Disks means that striping more than 8 is really not worth it for the small percentage performance gain.
So now we can ask the 64 million dollar question...
The test system was an ASUS CrossHair Mobo with a dual core 3.0 GHz (6000 Intelahertz) Daul core Athlon 64 processor not overclocked and 1GB of 667 MHz DDR2 in dual channel configuration and a crummy Geforce6 Graphics card with no graphics drivers installed. We used the latest 9.35 nForce 590 Mobo drivers and the latest Areca 1231ML RAID driver. We ran Windows XP SP2. We used a Raptor as the boot disk.
The true Hardware seek time of the New HyperDrive4 (revision3) as measured by the wonderful Data Transit Bus Doctor (30,000 Euro Bus testing hardware) is 1100 nanoseconds read and 250 nanoseconds write. HDtach3 gives a figure of 0.0 milliseconds. Computer Technical's H2BenchW gives a figure of 30 microseconds or occasionally of 20 microseconds, but these figures are just the minimum resolution of the Benchmark. Regrettably most RAID cards degrade this seek time by at least 10 microseconds.
We used Simpli softwares HDTach3.0.l.0 for the STR figures and CT Magazine's H2BenchW for the seek time and base STR and Windows application figures and Intel's IOmeter for the IOPS figures. Here are all the results in table form.
|2 WD Raptors||8 WD Raptors||1 HD4||2 HD4 RAID0||3
|Base STR (H2BenchW) MB/s||77||150||590||140||244||243||486||486||729||877||728|
|Effective STR (HDTach) MB/s||88.75||164||640||300||342||340||520||525||775||890||740|
|Burst STR (HDTach) MB/s||1262||1246||1240||1240||1253||1238||1246||1251||1245||1245||1250|
|Seek Time ms||8300||8500||8500||1||10||10||10||20||20||20||20|
|Swap File MB/s||86||103||120||207||280||280||348||351||269||267||269|
|Virus Scan MB/s||17||18.7||20.5||104||130||140||189||197||181||188||179|
|Combined Index MB/s||89.8||105.6||121.4||286.3||380.0||386.9||506.4||519.9||460.8||460.0||450.7|
|1K file IOPS||365||600||1,890||42,000||55,500||37,750||55,000||36,000||53,500||54,200||35,500|
|2K file IOPS||350||570||1,880||30,500||51,500||33,750||53,250||32,250||52,750||52,250||34,000|
|4K file IOPS||340||550||1,870||20,000||36,750||23,000||51,000||27,000||50,250||50,500||30,750|
|8K file IOPS||330||540||1,860||11,500||21,750||13,500||40,000||17,000||45,000||44,750||24,250|
|16K file IOPS||320||530||1,850||6,500||9,000||7,500||22,000||9,000||30,000||32,500||14,750|
|32K file IOPS||310||520||1,800||3,500||4,500||4,150||11,400||4,500||15,900||15,900||8,500|
All of the figures in the table are cache assisted other than the base STR figure. Here are some bar charts of the most relevant figures.
One HyperDrive is 235% faster at running your basic real world Windows apps than any number of RAID0 raptors on the fastest RAID cards known to man. So your office productivity will more than double even if you are presently using a huge hard disk array!!!
In fact given, the IOPS differential of more than 100x, we have seen speed advantages of 40x and more in the real world for SQL database apps and Multi user web servers and network servers etc.
5 HyperDrives in RAID5 are 428% faster than anything that can be done with hard disks and RAID cards.
So The HD4 has the capability to solve most IO problems!