Seagate Barracuda gen 7200.14 question.

irlwizard

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Hello I am trying VERY VERY hard to find a review of Seagate Barracuda 1TB (ST1000DM003) 7200.14 model with 64mb cache in Raid0 with two drives.

Here is the story, my desktop is getting old but it is still quite fast so instead of selling it for $300 I am going to take out my SSD and storage drive, buy two 1TB HDDs and Raid0 them, put my system in the living room and just have a PHAT game library on it to make it like a livingroom console.

Anyway. I want to compare if two 1TB Barracudas in Raid0 will be worth it compared to ONE 2TB Barracuda (good version with two 1TB discs, there is a bad version with 3 666GB/s discs). The only problem with raiding is that, since the read/write goes over 400mb/s (the 3TB do in Raid0 according to this review; http://www.hardwarecanucks.com/forum/hardware-canucks-reviews/49858-seagate-barracuda-3tb-raid-0-performance-unleashed-7.html) So I would have to use a SATA6GB/s controller. And I only have ONE on my motherboard (with two SATA ports, yay) but it is a MARVELL controller...

Marvell 9128 chip:
2 x SATA 6Gb/s connectors (GSATA3_6, GSATA3_7) supporting up to 2 SATA 6Gb/s devices
Support for SATA RAID 0, and RAID 1
* SATA3 RAID 0 4x and SATA3 2x performance are maximum theoretical values. Actual performance may vary by system configuration.
* SATA3 SSDs are not recommended for use in RAID 0 mode on Marvell SE9128 ports.
Source; http://www.gigabyte.com.au/products/product-page.aspx?pid=3304#sp

But will it support Windows 7 64bit? I have Ultimate 64bit.

NOTE: My manual says on page 92 that the INTEL controller can have STRIPE BLOCK SIZE set from 4kb to 128kb. But page 105 says the Marvell controllers stripe size for this controller ranges from 32 to 64kb. Honestly, I don't know what the hell stripe size is, but if it has an importance in Raid0 and 64kb is considered bad that I might be better of buying ONE 2TB and running it in the SATA3GB/s Intel controller.
 
Solution
We seem to be talking on different wavelengths.

A 3Gbps SATA link rate corresponds to 300MB/s, and 6Gbps to 600MB/s.

Your RAID controller communicates with each drive via its own 3Gbps SATA port at a maximum rate of 210MB/s. It then combines the two data streams to create a single 420MB/s data stream which it passes to the system via an appropriate bus.

The controller reads stripe #X from drive #1 and stripe #X+1 from drive #2 both at the same time.

As for stripe size, or whether to use the Intel or Marvell controller, I don't have any experience in this area.
AIUI, if you connect the two drives in RAID 0, each will have a maximum transfer rate of 210MB/s, giving a maximum combined speed of 420MB/s. Therefore each drive, and therefore the RAID, can still achieve this performance at 3Gbps.

As for stripe size, a 2TB RAID 0 is constructed by taking a 2TB logical volume and slicing it into segments called "stripes". The first stripe is written to drive #1, the second to drive #2, the third to drive #1, the 4th to drive #2, and so on.
 

irlwizard

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Thanks fza. I always thought 3Gbps SATA could only reach 300mb/s because no SATA 2 SSD ever goes beyond that. What is the real speed cap for 3Gbps and 6Gbps?

As for the stripe size what would you recommend I use if I decide to go with the intel controller, you can choose between 4 to 128kb.
And what is your recommendation if I go with the Marvell controller, choise is 32 to 64kb.


Like I said before, the machine will ONLY be used for games, it will just become a livingroom console so the aim is fast game LOAD times and saves, nothing else except sytem stability needs to be taken into consideration.
 
We seem to be talking on different wavelengths.

A 3Gbps SATA link rate corresponds to 300MB/s, and 6Gbps to 600MB/s.

Your RAID controller communicates with each drive via its own 3Gbps SATA port at a maximum rate of 210MB/s. It then combines the two data streams to create a single 420MB/s data stream which it passes to the system via an appropriate bus.

The controller reads stripe #X from drive #1 and stripe #X+1 from drive #2 both at the same time.

As for stripe size, or whether to use the Intel or Marvell controller, I don't have any experience in this area.
 
Solution

irlwizard

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Ah so a 3Gbps is 300mb/s PER PORT... Meaning a 400mb/s SSD will be caped on 300mb/s by itself. But two 210mb/s HDDs would run up to 420mb/s because they are plugged into different ports? If that was the case why did they even invent SATA6... No HDDs that I have herd of can run beyond 300mb/s (especially not 3 years ago when SATA6Gbps first came out) and raiding SSDs is idiotic because TRIM isn't supported in raid. :/