Quick question about ssd/raid/trim

A

Alxs

Limp Gawd
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Apr 7, 2007
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398
I know that there is actually no trim support for ssd raid, but I really want to do it. My question is : I know the ssd will have a performance drop from time to time, but if I format them, will they have their initial transfer speed back? I guess it would be yes, but I just want to make sure.

Thanks
 
if you mean you don't mind erasing all the data from the drives and starting from scratch, yes. Honestly, i'm not sure, it might be easier than that, but at the very least you can always turn off raid, run hdderase on the drives separately, reboot, and recreate the raid, and start reinstalling.
 
Yes, I meant erasing everything (fresh install). I read that the ssd could not go under 50% of it's performance by degradation. I also read that a maintained ssd could keep it's factory performance for a while (more than a year) and since I format more than one time a year, it should not be a problem. I just needed to make sure that the performance degrade was not lost forever. I also wonder if I'll need a raid card, I'm using a evga x58 mobo. I guess not since I would only use 2 ssd.
 
I also wonder if I'll need a raid card, I'm using a evga x58 mobo.
Click to expand...

No card needed.

You're always gonna lose some minor performance that won't come back but it should be unnoticeable in day to day usage.
 
Just to be clear, you can't just "format" the drives. You have to do a secure erase. Look for companies that provide tools that specifically do this for ease of operation. Intel just released a new version of their SSD Toolbox that has improved secure erase from within Windows.
 
Simply formatting the SSDs will not gain you the factory fresh performance again. You'll need to use a utility to send the SECURE_ERASE ata command to the drive. HDDErase is the current go-to tool to do this. HDDErase is a DOS based utility and as such you'll need to create a bootable DOS disk of some kind (A USB memory stick, flash card reader, even an old MP3 player will work good for this). The newest Intel SSD Toolbox 2.0 now has the ability to issue the SECURE_ERASE command to an SSD, but since it's a Windows based utility it won't do most people any good.

In an SSD, a secure erase basically wipes all of the 'pages' contained in the NAND memory cells (everything, user addressable and the hidden redundancy areas) and brings the drive to it's factory state with associated performance levels, ready to be partitioned and formatted and used again.
 
westrock2000 said:
Just to be clear, you can't just "format" the drives. You have to do a secure erase. Look for companies that provide tools that specifically do this for ease of operation. Intel just released a new version of their SSD Toolbox that has improved secure erase from within Windows.
Click to expand...

Except that since 99.5% of people use their SSDs as an OS drive this feature is essentially useless.

Unless you want to either:

1. Remove the drive and cart it to another Windows based machine to run the SSD Toolbox on.
2. Install Windows on another hard drive just so you can run the SSD Toolbox.

I guess it's good that they added secure erase to the toolbox, but I can't see how anyone's going to be able to use it. :D It's like wipin' before you poop, it just doesn't make any sense.
 
serpretetsky said:
if you mean you don't mind erasing all the data from the drives and starting from scratch, yes. Honestly, i'm not sure, it might be easier than that, but at the very least you can always turn off raid, run hdderase on the drives separately, reboot, and recreate the raid, and start reinstalling.
Click to expand...

breaking the array to trim it is the same thing as formatting it and starting from scratch; yoru data will be gone after either of those two things. you can not remove a disk from an array, 'clean' (write to) it, and then throw it back in the array. the disk would have to be rebuilt. if you had a RAID0 it would be trashed.
 
Use the Sandforce SSDs for RAIDed systems; they have additional spare area thanks to compression which you get even without TRIM; cool huh?
 
I guess it's good that they added secure erase to the toolbox, but I can't see how anyone's going to be able to use it
Click to expand...
You're probably correct about the 99% but I do feel that many will be more comfortable working within Windows rather than a DOS bootable program. Many probably have trouble making a bootable ISO. :)

ATM I have 3 separate OSs (two are SSD RAID0) and I have a feeling the new toolbox feature will come in handy. :)
 
westrock2000 said:
Just to be clear, you can't just "format" the drives. You have to do a secure erase. Look for companies that provide tools that specifically do this for ease of operation. Intel just released a new version of their SSD Toolbox that has improved secure erase from within Windows.
Click to expand...

im pretty sure intel's newest firmware for their drives trigger a secure erase when you do a format (at least for windows 7). I dont remember where i read this. This doesn't apply to any other ssd's
 
serpretetsky said:
im pretty sure intel's newest firmware for their drives trigger a secure erase when you do a format (at least for windows 7). I dont remember where i read this. This doesn't apply to any other ssd's
Click to expand...


I find that highly highly unlikely.

'Soft' formatting is an OS level operation and from the drive's standpoint it has no way of knowing what's happening other than a bunch of sectors are being written to (zeroed) sequentially. And in the case of a 'quick' format which is done 99% of the time all that's done is the MBR, MFT (or FAT) is cleared of entries.

Say theoretically someone did try to implement something in the SSD's firmware to initiate a secure erase whenever a traditional soft format was done - the number of 'false positives' would be so high that the drive would be secure erasing itself at random all the time.
 
Read that somewhere too; and it's not that hard it requires the formatting to use TRIM instead of zero-write if it detects an SSD. FreeBSD's newfs command now also includes a TRIM-surface option when creating a new UFS filesystem. So that kind of works the same way i guess.

The way Windows 7 does formatting did change relative to Vista; in Windows 7 it would zero-write instead of just read. But perhaps that was not the only change they made; and they also made it so that even a quick format would TRIM the whole surface LBA; which should be a matter of seconds.
 
Blue Falcon said:
I find that highly highly unlikely.

'Soft' formatting is an OS level operation and from the drive's standpoint it has no way of knowing what's happening other than a bunch of sectors are being written to (zeroed) sequentially. And in the case of a 'quick' format which is done 99% of the time all that's done is the MBR, MFT (or FAT) is cleared of entries.

Say theoretically someone did try to implement something in the SSD's firmware to initiate a secure erase whenever a traditional soft format was done - the number of 'false positives' would be so high that the drive would be secure erasing itself at random all the time.
Click to expand...
http://www.anandtech.com/show/2865/2
there ya go
 
serpretetsky said:
http://www.anandtech.com/show/2865/2
there ya go
Click to expand...

TRIM != the ATA 'SECURE_ERASE' command.

Although most of the performance is restored because Windows 7 is issuing the TRIM command during a format (which is actually pretty cool, just goes to show how SSD aware Microsoft made Windows 7), it's still not quite the same.

TRIM is a filesystem / OS level command, 'SECURE_ERASE' is a single ATA command that is sent to the drive and (in the case of the SSD) sets about doing what amounts to a complete wipe of the NAND - all pages, blocks, yadda - EVEN the 'extra' or 'redundant' memory that's normally not visible the host machine. (This is the 'extra space' that helps with wear leveling when you have an SSD loaded to full capacity).
 
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