SSD Raid0 write speed

roadwarrior7

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Hi, I'm using two 50Gb Vertex2 in raid0 config,
And i think im getting decent read speed, but im getting really crappy write speed.

Seq read: 354.2 MB/s
Seq Write: 130.7 MB/s
512K Read: 330.7 MB/s
512K Write: 116.3 MB/s
4k Read: 22.12 MB/s
4k Write: 87.34 MB/s
4k QD32 Read: 178.3 MB/s
4k QD32 Write: 90.12 MB/s

Drive is 88% full(82/93gb)

I only use this drive for pretty much windows & Cinema4D/Video&music editting softwares.

How do i get it fixed? >.<
Thanx!
 
1) Because you are using raid, you can not get "trim" support.
2) Because your drive is nearly full, there are few free blocks available to write to so a read/rewrite operation must be done. Trim support would have made more blocks available.

Possible solutions:
a. Split the drives back to 2 normal drives with trim support.
b. Run a cleansing utility to clear up free space.
c. Sell the drives, and get a single 120gb drive, using trim.
 

roadwarrior7

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Thank you for the reply! I'm total nub when it comes to storage.
What is Trim? And... is it impossible to get trim support in raid config?
Thank you!
 
Trim is a command that can be given to a SSD to release nand blocks when a file is deleted. Without trim, the block has to be read and rewritten which is time consuming.
There is no problem when a ssd is new, and there are plenty of available nand blocks.
To enable trim, you need to be using windows 7, and the sata mode must be AHCI(not ide or raid). That will give you the needed drivers.

It is difficult to change to AHCI without reinstalling windows-7.
Corrently you can not get trim support for drives involved in a raid array.

Why do you want raid-0 anyway?
Are you experiencing some sort of performance problem?

Most of what we do is small random reads and writes. Perhaps 90% The benefits of raid-0 come with large sequential reads and writes.

There are some SSD's out there that do something called garbage collection as a help for those who can not use trim, like mac users.

 

roadwarrior7

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I do lots of rendering on Cinema4D, and it takes bloody ages...
So i asked around, and one of my friend told me that using ssds on raid config could help.
I am not completly sure how much performance boost i can get by using SSD, since rendering is cpu heavy job...
So yea, i started using SSD to cut down some rendering time.
 
Were you successful in cutting down your times using a ssd?

If so, look for Intel's next gen 510 series SSD :

http://www.hardwarecanucks.com/news/storage-news/intel-rumoured-launch-510-series-ssd-march-1st/

Your cpu is a very good one. A change there may not be worth it.

The new sandy bridge cpu's are 15% more efficient, clock for clock, and OC to 4.5 and can probably do your job a bit faster. Look for Cinema4D specific benchmarks to see if a change might be worth it to you. Revised P67 motherboards for sb may not be available for a month or so.

Larger single SSD's will usually perform better. Internally, they have more nand chips that they can access in parallel. Sort of an internal raid-0.
I once had two X25-M 80gb drives in raid-0. I did it to get a single image, not for performance. Later I changed to a single X25-M 160gb drive, and performance seemed about the same.

The problem with benchmarks is that they do not measure YOUR workload.
 

roadwarrior7

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Yes, it did cut down the rendering time, but its still super long... Normally it takes around 10~12hours to even couple of days.
So, yea... I am always trying to figure out a way to cut down the time. Only stuff that affects rendering time is CPU, ram and hdd i think...
I have 8gb mem, on 2.2ghz, and as you said, CPU is pretty good(though thinking of getting BD when it comes out, if benchmark looks fancy),
so only thing i can really improve at the moment is hdd/ssd. So yea... >.<
 

CopaMundial

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When you do go to upgrade your CPU eventually, you should consider a dual-CPU option like the Xeon offerings would support.
Definitely a more expensive build than an individual would want to pay, but I doubt you're playing around on Cinema 4d just for fun. If it's a business application, then it's easier to justify the cost b/c faster rendering would allow you to complete more jobs with higher quality (b/c some of the time savings could be re-invested into improvements on the animation). So that would mean you would end up making more money and one extra job would probably pay for your Mobo/CPU's. Plus you may be able to find incentives where you could claim it as a business tax deduction.

That is, of course, assuming you're getting paid for your animation work. If you're just a hobbyist, then you're probably going to be stuck with long wait times because I really doubt the RAID write times are what's holding you up.