raid vs. 3.0gb/sec sata

[jueston]

what would be faster?

4 * 40BG IDE harddrives set up in RAID 1+0 on an PCI raid card or a 3.0GB/sec sata drive?

the 40GB harddrives would most likely only have an 8MB cache where the sata harddrive would have a 16MB chache.

 

[slicessoul]

In RAID 1+0, read performance is better than just a single HDD. Write performance is slower than single drive (correct me if i'm wrong) and using more CPU power.

For a normal utilisation i would prefer take single drive SATA II. Besides that it's more cheap.

ex: 4 times 40 gigs HDD cost around 100$. For 100$ i can have 320GB HDD with SATAII and NCQ facilities.

 

[darkstar782]

Incorrect, in RAID 1+0 you have two RAID 0 arrays mirrored. (or two RAID 1 arrays striped)

Write performance is the same or negligibly worse (due to CPU overhead) than a RAID 0 array of two of those drives, read performance is slightly better.

However, if the controller is a two channel controller and you have two drives on each PATA cable, performance will be crap for the entire array.

Also, those 40GB drives are old and their read/write performance is probably dire.

The SATA drive would probably perform better to be honest, although the 3.0GB/sec part (SATA2) is completely irrelevent - see here:

Firstly, it doesnt matter.

SATA2 is completely pointless for the sort of applications you are talking about. There is no difference whatsoever in performance of a single drive on an SATA2 interface or a single drive on an SATA1 interface.

Even a 4 disk RAID 0 array will be exactly the same performance wether SATA1 or SATA2.

The only time there will be any difference is when using a device like this to connect more than 1 hdd to a port.

As there is no difference, who cares if a drive runs at SATA1 or SATA2 speeds? The fastest IDE drive is the Western Digital Raptor - an SATA1 drive