M4 & Raid .. noobish

[cytg111]

So, the M4 512g is at a really sweet price point and seriously thinking about getting rid of my spindles and go SSD only.

It is just that 512G is not all that much, and I would like to have just ONE drive, not 2-3-4 and splitting everything up. No, I want 1-one drive where I will put all my stuff, and I figure that that 'one' drive needs to be bigger than 1T.

That leaves me with raid, right? I cant imagine I could sleep well going raid0 all the way, but I recently bought a NAS where I am running raid-5. 4 discs and get the volume of 3. (everything 'streamable' runs from here, wont waste precious ssd space)

So, would it be nuts to go for 4 M4's, raid 5'em, for a total of 1.5T harddrive space?

I am looking for arguments NOT to do it .

ps. bonus question .. if an M4 decides to go back, i can swap any SSD with an equal or larger capacity into that raid right?

 

[Coup27]

I would get 2 x m4 in RAID0 and use your NAS to backup your data. That way you get your data backed up without basically doing it on an SSD.

 

[cytg111]

I would get 2 x m4 in RAID0 and use your NAS to backup your data. That way you get your data backed up without basically doing it on an SSD.

Yes, thought of that .. But I hate to say it, i Lack the dicipline.
I am just not that organized, I try to control chaos (and often fail).

ps. and i need in excess of 1TB.

 

[Coup27]

To be honest I have just moved from a single Samsung 830 128GB to two of them in RAID0 and I can't really tell the difference..

 

[cytg111]

To be honest I have just moved from a single Samsung 830 128GB to two of them in RAID0 and I can't really tell the difference..

I get it .. raiding in this scenario is not about the performance, it is about having the space I need on ONE volume. That is it.

ps. I read somewhere that raiding could actually hurt random iops .. is that true? If so, by how much? Is it a factor to consider ?

 

[Coup27]

My random read on a single drive using CDM was 24.50MB/s. With two in RAID0, it was 23.13MB/sec.

I know that RAID0 won't improve random reading but I haven't read of it making it worse.

 

[cytg111]

How about bootup time ? I've read ppl complaining about the time it takes for a "raid array to initialize".. or something like that. What have you noticed going raid ?
My main pc stays on for the most time, but still..

 

[Coup27]

Overall POST time has increased by about 3 seconds. This is the time needed to boot the previously dormant RAID controller. I haven't finished loading up my new installation yet but on initial findings there doesn't appear to be any noticeable difference in overall feel. I'll give it a month but if I still think the same I'll take it apart and use 1 drive as my "speed up repairing someone else's computer with my spare SSD drive".

 

[cytg111]

Ok, thx

 

[greenhawk]

I know that RAID0 won't improve random reading but I haven't read of it making it worse.

happens. CPU overhead working out which drive has the data to request. Also using a different controller vs previous numbers can also effect any bentchmark being used.

 

[bryanW1995]

How about bootup time ? I've read ppl complaining about the time it takes for a "raid array to initialize".. or something like that. What have you noticed going raid ?
My main pc stays on for the most time, but still..

My raid 0 m4's boot very fast, much faster than only one m4 did.

 

[Zap]

Yes, thought of that .. But I hate to say it, i Lack the dicipline.
I am just not that organized, I try to control chaos (and often fail).

In Windows 7 you can set up Backup and Restore to do backups for you. You just got to set it once.

Here is where I say my obligatory "RAID is not a backup!" You were looking to do RAID5? It can help with your uptime if a drive dies (depending on the controller), can increase performance and increase capacity over a single drive. It will not help if you accidentally delete something, or get some malware, or the partition corrupts itself.

How about bootup time ? I've read ppl complaining about the time it takes for a "raid array to initialize".. or something like that. What have you noticed going raid ?

Adds a couple seconds.

Note that while motherboard chipset RAID is very suitable for RAID0, while they often support RAID5 I'm not sure they're the best at that particular task. Perhaps someone who has more experience with dedicated RAID cards can chime in on the science behind that.

 

[cytg111]

thx for all your replies .. back in the thinking box.

 

[Coup27]

cytg111 I've pretty much finished installing programs and what not and I am not convinced there is a noticeable real world difference for me. My system before was very fast and this one is also very fast. It was more an experiment to be honest because I aquired another drive from work and never done a RAID array at home before so thought I would see what it's like.

 

[_Rick_]

Don't go RAID, go JBOD.

Window should just let you extend the volume across multiple physical disks.
Don't waste any space on redundancy, and don't waste any cycles on calculating checksums. Not to mention, that RAID 5 can be quite slow at time, depending on the controller.

 

[bryanW1995]

JBOD increases the risk of failure vs keeping the drives separate, and if there is a failure you have no control over what was lost. May as well go RAID 0 unless you're using different-sized disks.

 

[cytg111]

JBOD

- That had me going for a second, but reading up on it, there is no gurantee what ends up where, thus giving me the same reliability as the raid0 setup, that is, one drive dies, all data dies.

I am contemplating a raid0 with 2 or 3 of these M4's and then bite the bullet and get some backup going .. backups could, at first, go to my current 320 .. but fail0r math of putting 3 drives in raid0 does not induce a happy face.

Maybe I should just suck it up and forget about the 'one volume to rule them all' and live with independent drive letters ...

 

[Diogenes2]

To be honest I have just moved from a single Samsung 830 128GB to two of them in RAID0 and I can't really tell the difference..

You didn't notice you doubled your capacity ?:biggrin:

 

[kalrith]

In Windows 7 you can set up Backup and Restore to do backups for you. You just got to set it once.

Here is where I say my obligatory "RAID is not a backup!" You were looking to do RAID5? It can help with your uptime if a drive dies (depending on the controller), can increase performance and increase capacity over a single drive. It will not help if you accidentally delete something, or get some malware, or the partition corrupts itself.

This.

RAID5 is a good choice if you can't afford downtime. However, if you're dealing with data that you don't want lost, then you would still need a backup even if you had RAID5. If you can afford downtime, then you can go with RAID0 plus backup and save some money.

I personally use an external backup drive that backs up my data once per month, and then I keep the drive at work. That way I won't lose all pictures and movies of my son in a house fire. My data doesn't change that often, so once every month or two is sufficient. I could live with two months of data loss, but I know that many people can't.

 

[bryanW1995]

- That had me going for a second, but reading up on it, there is no gurantee what ends up where, thus giving me the same reliability as the raid0 setup, that is, one drive dies, all data dies.

I am contemplating a raid0 with 2 or 3 of these M4's and then bite the bullet and get some backup going .. backups could, at first, go to my current 320 .. but fail0r math of putting 3 drives in raid0 does not induce a happy face.

Maybe I should just suck it up and forget about the 'one volume to rule them all' and live with independent drive letters ...

The key with RAID 0 is to get the most reliable drives possible. Crucial, Intel and Samsung look like the most reliable of the current 1st gen SATA 6gb/s generation, though some others look to be making a strong push now to join the party. And, as mentioned, backup is key.

 

[_Rick_]

- That had me going for a second, but reading up on it, there is no gurantee what ends up where, thus giving me the same reliability as the raid0 setup, that is, one drive dies, all data dies.

I am contemplating a raid0 with 2 or 3 of these M4's and then bite the bullet and get some backup going .. backups could, at first, go to my current 320 .. but fail0r math of putting 3 drives in raid0 does not induce a happy face.

Maybe I should just suck it up and forget about the 'one volume to rule them all' and live with independent drive letters ...

Nope, you can recover some data, if a drive fails, as long as file system fragmentation is low. Recovery will be hard, but not as hard as when you miss every other piece of a file.

But yes, a 2 TB hdd as backup and 3 512GB ssds in RAID0 is probably more reliable.
Independent file systems can also work without independent drive letters. You can mount file systems into folders. Drawback is that some installers only check the root drive letter for free space and ignore free space in the folder. Steam used to do that at least, not sure if it's still the case.

I'm currently quasi SSD-only with spindles all in my NAS, but then that NAS is where my user profile resides, so I only need a bit of place locally for applications. No point in storing data on SSDs. Just too expensive. Invest the money into proper RAID and backup RAID instead.