I finally joined the 21st century and bought an SSD for my laptop. The catch is that the existing HDDs are 2x500GB Raid 0. I don't understand enough about how raid works (especially Raid 0), and I don't want to mess something up. My aim is to clone the existing boot drive onto the new SSD. Yes, I did a Google search, but I don't really understand what's going on.

7/2/2018 9:15:50 PM

that's a terrible idea and will lead to misaligned IO. backup your data to an external drive, then reinstall the OS onto your SSD and then leave one of the 500s in as extra/backup space. once your OS is reinstalled, copy your data back. keep the other 500 as an external backup

7/3/2018 12:53:47 AM

You can do a direct to SSD clone that forces proper alignment. However, why trouble yourself. Do a fresh install then copy over. It is the only way to be absolutely sure everything will work out perfectly

7/3/2018 2:04:18 AM

Hopefully quick explainer:

All data in computers is "chunked". Chunks go by names like blocks and pages, but the idea is metaphorically the same as a row of tiny high school lockers. When you need to store something (and assuming most things need more than one locker) the computer breaks it into a bazillion pieces, makes a record of the locker where the file starts, then leaves a Post-It in every locker where it's next chunk is. Its not always efficient to search around for a huge swath of space large enough for the whole file to fit neatly. If you remember old school defrag you could graphically watch the hard drive reorganize things so they were all in a nice row after the fact.

RAID, in it's various levels, effectively perform the same trick: recruiting your friends to help you stuff lockers. Except compys don't necessarily organize like we might. If you ask it to store a dumptruck of data, it doesn't have enough buffer to look at the whole dump truck, it just looks at each piece that comes off the truck, busts it in half, and sends one half to hall A and one half to hall B. It's efficient, it's fast, but ultimately there's a lot of management overhead. Equally, it's extremely high overhead (and sometimes dangerous) to do the equivalent of defrag on this format - you need very specialized tools that understand the entire relationship of all the hallways, not just the post-it sitting in front of it's face.

This also makes it hard to copy. You can't just go locker by locker following a single chain on a single hallway. Every piece of data was busted when it came off the truck. Hall A locker 1 has a Post-It pointing to A2, but A1 needs to be combined with B1 before moving on (because we busted in half to get it off the truck faster.) This is the alignment problem being referred to.

To fix, we need to leave these mated RAID hallways alone and instead build a 3rd hallway. Let the controller sort out reading and reassembling the data, then we put it completely reorganized into the new hallway.

Now the rub: if the controller is hardware, you might be OK. Boot from a USB stick Linux and let the cloner run as a 3rd party to the whole affair similar to hired movers. If it's implemented in software, that means the OS needs to be alive and booted - cloning alive and booted RAID volumes should be avoided. If your machine has a 3rd drive bay not on the raid controller I might try it though. Worst case it doesn't work. Still have all your data. But if you need to reconfigure sata ports out of the controller to swap in the new drive after clone (you don't have a truly spare port) you're playing with fire. Dont touch that controller/config until you're sure you're ready to lose both those drives.

Long story short: don't use software raid unless absolutely necessary. Don't ever, ever use software Raid for a bootable drive. In most cases don't put your OS on raid unless you're really adept and know what you're doing. SSD boot drive and raid for your storage drives is a much better life choice.

7/3/2018 4:34:05 AM

Thank you all for the explanations. This is more cumbersome than I initially good it would be. The laptop came configured for Raid 0, but it begs the question of what people do when one of the drives eventually fails?

7/3/2018 7:34:26 AM

They lose all their data. That's how RAID 0 works. If they wanted redundancy, they would use RAID 1.

7/3/2018 11:50:20 AM

1 - buy this: https://www.acronis.com/en-us/personal/computer-backup/ (or maybe this: https://www.acronis.com/en-us/personal/disk-manager/)
2 - plug the SSD into a dock
3 - ?
4 - Profit

7/3/2018 2:15:44 PM

If I'm looking to put in an SSD and I remove all the data from the second drive, is there any way to unconfigure them as RAID since RAID 0 is supposed to be a performance thing?

7/3/2018 6:32:55 PM

After data migration, there should be a tool in your BIOS to manage the RAID array.

7/4/2018 11:23:26 AM

you missed the days of hardware managed arrays on a 1995 controller not made any more...

7/4/2018 1:31:50 PM

I suppose I did. This shit is nuts. I comprehend why folks like RAID 1, but in an era of SSDs, RAID 0 just seem more like a liability.

7/4/2018 9:27:11 PM

Quote :

"but in an era of SSDs, RAID 0 just seem more like a liability"

Yeah it seems like a relic for consumer uses at least. How old is your laptop, and what is the make/model?

7/4/2018 11:48:07 PM

anyone using unRAID?

https://lime-technology.com/

7/5/2018 6:10:24 AM

sounds like ZFS or the file system that windows home server used to use

7/5/2018 11:12:14 AM

^, ^^
Doesn't unRaid use ButterFS?

If I had a machine with multiple processors and 8+ drive bays I really would like to try setting it up for something similar to the old roaming desktops from Novell. Just put a random chromebook or used all-in-one in the kitchen and living room and seamlessly move between physical locations all logged into the same virtual machine.

Unfortunately my current storage solution wasn't up to the task and the other machine tends to pay bills, so I leave it be.

Quote :

"I comprehend why folks like RAID 1, but in an era of SSDs, RAID 0 just seem more like a liability."

For valuable things, I tend to agree. An M.2 drive closing the gap on 2GB/s is more than enough for your precious OS and a copy of Counterstrike. Honestly, I have a 500MB/s SATA SSD in one machine and a M.2 in the other; it's hard for me to tell an appreciable difference starting things up. Maybe a second or two.

However... if you need swap/working space, I wouldn't hesitate to RAID0 a fist full of smaller SATA SSD's. Price/GB is significantly cheaper than M.2 drives. During the summer I do some freelance audio editing and nothing is more important that storage speed. Some edits used to take 5-6 minutes on my workstation when I was using 10K RPM drives in RAID0. I've changed nothing but the storage and now the same edits are sub-10 seconds on SSDs. Used to have to queue things up to process overnight, now they can usually render in the background while I import the next one off SD cards.

Its all about balancing your machine. If you render a lot of A/V and your processor is starved by disk, give it more disk. Get the most out of those $'s you spent.

7/5/2018 7:47:35 PM

Quote :

"How old is your laptop, and what is the make/model?"

2012 MSI GT60 https://www.msi.com/Laptop/gt60-0nc.html. Currently Windows 7, but I will switch it back to 10 sometime.

7/7/2018 7:17:18 PM

^ that link says you could order it with dual mSATA SSDs (the proceeding standard to m.2)

You should go for broke: clone it to an external drive, install 2 SSD's, RAID 'em up, clone it back.

7/8/2018 9:07:23 PM

lol I had the same thought

7/8/2018 10:39:47 PM

I wouldn't spend any more money on a 3rd gen i7 and a 5 year old battery

7/9/2018 8:06:03 PM

I love how smoothcrim's answer is spend MORE money.

[Edited on July 9, 2018 at 10:46 PM. Reason : an SSD is far from an unreasonable upgrade for that machine.]

7/9/2018 10:45:46 PM

no, you misunderstand. I meant the single sata ssd was a fine upgrade, rather than buying 2 msata ssds to raid

7/11/2018 2:06:29 PM

I agree that the 3rd gen i7 may not be cutting edge, but I never use the battery (I do let it run down and charge it up periodically though)

7/16/2018 8:32:37 PM

Quote :

"rather than buying 2 msata ssds to raid"

That was a joke

7/16/2018 10:23:38 PM