Mix Intel SSD X25-M for RAID 0

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Hi guys,
I had a quick question about mix and matching ssds for RAID 0 performances.
I already own the first Generation 80GB intel x25m (G1).
I see that on amazon, the new G2 intel 80GB x25 are much cheaper. Would if be a good idea to mix the two different generation x25-M and use it in a RAID 0 configuation?
What would be the performance gain? Will the first gen x35m be a bottle neck? Is it a bad idea to mix these two ssd? Should I get first gen x25m to RAID with the one I already have?

 

raid 0 with SSD is not needed nor really beneficial aside to say you have it.
however, to answer your question....
if you so desire to raid the SSD's, id go with identical drives regardless. i would not mix and match SSD's in this case.

 

Well, I want to put this into the M17x. But why shouldn't I RAID 0 an SSD? How is it not beneficial? I mean, I'll get exceptional speeds either way right?

Thanks for your quick reply ryujin! =)

 

Because your single SSD is already blazing fast. The faster each individual drive is the less speed you're gaining by setting them up in RAID 0.

If an SSD is already loading data in say 4 seconds you'd only gain 1 or 2 seconds by setting two SSD up in RAID 0. Not worth the cost or the loss in storage.

 

Even if you gain 10% performance, it's amazing... RAID 0, loss of storage? Are you confused with RAID 1?

 

10%? Dropping 4 seconds to 3.6 seconds is not an amazing gain in performance.

2 SSDs in RAID is a loss in storage vs. 1 SSD for apps and 1 much cheaper large capacity HDD for data files, movie, and music storage.

 

Ok, I understand what you mean yet I would still recommend SSD RAID 0 config for people who do lot's of photoshop, video editing. Since I have my Samsung 256gb SSD, you can't imagine the gain in performance for those apps. I can actually copy multiple files now without a drop in copy performance. It's just amazing so 10% on 4 seconds yes, that's low but what about on the files that still take me 10 minutes to copy, move, edit. That's a 1 minute gain and so much more throughout the day.

 

TBH if you say this i highly doubt that you tried with only 1 SSD .

Theres no point in raid 0 ssd.

 

There is a point with RAID 0 SSD.

Little test: write speed of the samsung 256gb SSD: 188mb/s
write speed of two samsung 256gb SSD RAID 0: 276md/s

Yes there is a point...

 

And?, the big plus of SSD is access time not the speed.

I had 2 vertex in raid 0 in my desktop, 500mb/s and whats the difference to a single vertex?, none.

1000000PT/s doesn't matter if your files are sub 100mb .

And BTW... You need to optimize your SSD's, that's pretty slow for 2 drives raid 0.

 

While your raw speed may go up with raid 0 (and maybe down if you do not have a good controller) it will add the latency of the raid into the mix and I think that would hurt you more than any of the bandwidth boost you would get.

Unless your working with some really really large files or something that require a ton of raw transfer speed and no seek then I would not do it.

 

Ok, then yes I agree with you... But I use a lot of files greater than 250mb which is why I was saying I love the RAID 0 on my SSD.

Now for sure, it will slow down a bit the seek time and yes it is useless on games...

 

See above post

 

A file that takes you 10 minutes to write at 188mb/s would be about 113 Gb and is going to take up almost half of your 256gb of SSD storage. ;þ


A more reasonable 1Gb file, on the other hand, that took 5.3 seconds to write with 1 SSD now takes 3.6 seconds with 2 SSD in RAID 0.

$400 for 1.7 seconds/Gb.

 

Your calculations are off because you assume, the only thing I am doing is transferring 1 file at a time.

This is where I found the SSD RAID to be amazing is when transfering many large files at one time... To me it's worth the money but I understand it's not to others.

 

Most important > Southbridge ICH 10 to see some gains at all

 

But I'm talking about Intel's X25-M here - which has one of the best controller in the SSD world to date.
Samsung has a good controller as well.

In that case, does your comment still hold true that it will hurt me more than I gain from it?

 

His talking about the RAID controller...

 

I guess then, how good is the RAID controller that M17x comes with?

 

Yes the raid controller is what I was speaking of.

With hard drives they worked fine but with a top notch SSD your pushing the limits of what the controller can do without slowing the SSD down.

How good is the one in the M17X? I dont know, will it slow down your SSDs? I dont know. I simply stated its a very realistic possibility.

I would be more concerned with the access time than the raw speed. Most controllers will probably handle all/most of the speed of 2 SSD combined, but if it adds even 1ms of latency into the mix your blazing fast 0.1ms seek time on your SSD (the main reason SSD are so fast) is now 1.1ms so thats a pretty big loss in performance on a SSD grading scale.

But like I already said in the last post if your main goal is faster transfer of some very large files on a regular basis, the trade may be worth it for you.

Also do not forget the native disadvantages that Raid 0 has always had. If one disk fails you lose all your data.

 

I was doing a bit of reading lately, and noticed that Western Digital launched a 1 TB 2.5 inch HD. [Link]

I was going to get the Raid 0 SSD's from M17x customization (with a 2TB external)...but reading this, and considering the 1TB 2.5, is swaying my opinion. Would Raid 0 SSD's really not be much of an improvement, even with Windows 7 being more optimized for SSDs?

Also...then I began to read that Hitachi released a 2 TB 3.5 inch HDD. [Link]
I'm going to assume 3.5 inch is too thick for laptops? (I'm a first-timer with notebooks).

 

You know, I never understood that... What does it mean if one disk fails?
Are we talking about a OS freezing and then you have to hold power to reboot?
And how likely is it that twin Intel SSD will fail on me (If this occurs) compared to some spinning hard drive ?

 

I believe its not an OS freeze, and more like a hard drive failure.
I'm pretty certain this is less likely to happen compared to spinning HDD's

 

if a disk dies you lose the data on both, as the 2nd disk still functional only has half of the data since it was striped between the two drives.

SSD may not up and die like a HDD but we have had SSD fail on people so it can happen.

 

I'm still curious though, about the performance benefits with windows 7 (being optimized for SSD's) from single vs a raid 0 config?

On the topic of the raid controller..wouldn't Dell provide a raid controller suitable for the performance of 2 SSDs when they offer a dual SSD option? basically no latency problems..

Lastly.. I was under the impression that 2 SSD's in Raid 0 would perform twice as better than 1(not 10%)? I researched this on multiple websites a week or two ago..but I may have misunderstood?

 

Raid will always double your latency and sometimes it triplicate.

The RAID controller in M17x is software so... I can't really say that it isn't going to be a bottle neck, would need to be tested.

And 2 SSD in raid 0 would give twice the speed, but this doesn't happens for 3, 4 hds.

 

As extra info:

http://enthusiast.hardocp.com/article/2009/07/06/ssd_raid_scaling_under_windows_7/4

 

Latency with Raid and Single SSD

 

Yeah I'm sure that you can see real world difference between 250mb/s and 500mb/s .

You never used a ssd do you?

 

Its going to be something you have to test for yourself. SSD do work well in raid, but they also work well alone

I have seen them perform as they should on high end dedicated desktop raid controllers, the ones in a laptop may/may not be as nice.

Try it and see, and if you dont like it just undo it.

me personally I would use 1 SSD and 1 large hdd to offset the capacity lost in a small SSD.

 

I am planning on a 256 gb ssd and a 500gb 7200rpm hdd in my m17x

I don't see Raid being necessary (and I wont be able to afford). I cant imagine needing more performance than a single ssd would offer - I will still be blown away by the increase over a standard hdd

 

you want a load of throughput RAID 0
if you look at latency just a single with a massive harddisk should do the job

I am running Intel X25-M Postville 160GB the moment

 

Yeah I'm pretty sure that everybody here move 10GB files all day long...

 

you are only looking from your point of view..

if your are heavy in graphic design or video editing yes its verry important
not everybody is using his Alienware to play games