SSD and defrag - question

dlb · Mar 23, 2012

I've read online that defragging a solid state drive is not only unnecessary, but is actually a bad idea due to the way SSDs manage the data stored on 'em. I know that Vista and Win7 have a built-in defrag that runs when the PC is idle, and I think Win7 has a boot-time derfag too. Should these built-in background defrags be disabled when running an SSD?

cabbiinc · Mar 23, 2012

I could be wrong but I don't believe that there is an automatic defrag or even a boot-time defrag in Vista or Win7. At least not on by default. Are you sure you're not thinking of iobit Smart Defragger or the like?

plodr · Mar 23, 2012

Double check it is NOT scheduled to run
http://www.sevenforums.com/tutorials/3292-disk-defragmenter-schedule-turn-off.html

Rikky · Mar 24, 2012

Drive wearing on any SSD based drive will always be a ghost in the back of your mind. Here are some recommendations and tips for a long lifespan and optimal performance. Basically, what is needed is to eliminate the HDD optimizations within Vista (that cause lots of small file writes like superfetch and prefetch), things like background HDD defragmentation (that causes lots of small file write drive activity). In short (and this is for Vista and Windows 7):

Drive indexing disabled. (useless for SSD anyway, because access times are so low).
Prefetch disabled.
Superfetch disabled
Defrag disabled.

So make sure you disable prefetchers. Also, especially with Vista and windows 7, make sure you disable defragmentation on the SSD disk. You do not have a mechanical drive anymore so it is not needed, let alone you do not want defragmentation to wear out your drive, and Vista does this automatically when your PC is in idle (picking it's nose).

Don't get me wrong though, you could do a defrag without any problems, you just do not want that to be regular.

For Superfetch/prefetchers and other services, at command prompt just type: services

Use Windows 7 / Vista's services to disable them. To disable defragmentation:

Windows 7 and Vista Automatic Defrag:

1. Click Start
2. Click Control Panel
3. Select the Control Panel Home
4. Click System and Maintenance
5. Under the Administrative Tools section at the bottom, click Defragment your hard drive
6. You may need to grant permission to open the disk defragmenter
7. Click or unclick Run automatically (disable) depending if you want this feature enabled or disabled.
8. Click OK

OR alternatively at the Vista start prompt just type : dfrgui

Now over time your SSD will get a little fragmented but it's NAND flash and there's no mechanical head moving back and forth to access that data so just leave it disabled.

Windows 7 and the SSD TRIM feature

Windows 7 and Windows Server 2008 R2 support the TRIM function, which the OSs use when they detect that a file is being deleted from an SSD.

When the OS deletes a file on an SSD, it updates the file system but also tells the SSD via the TRIM command which pages should be deleted. At the time of the delete, the SSD can read the block into memory, erase the block, and write back only pages with data in them. The delete is slower, but you get no performance degradation for writes because the pages are already empty, and write performance is generally what you care about.

Note that the firmware in the SSD has to support TRIM.

TRIM only improves performance when you delete files. If you are overwriting an existing file, TRIM doesn't help and you'll get the same write performance degradation as without TRIM. In AHCI mode TRIM is activated automatically.

Enable AHCI

The last and great tip we want to give you to gain a little extra performance boost is that you should enable AHCI mode. AHCI mode can help out greatly in performance for SSDs. Now, if you swap out an HDD for an SSD with the operating system cloned and THEN enable AHCI in the BIOS, you'll likely get a boot error / BSOD.

The common question is, is there a solution for this ?
To answer that question (and as we do safely with all modern chipsets) there is a way to safely enable AHCI mode. Here we go:

1. Startup "Regedit"
2. Open HKEY_LOCAL_MACHINE / SYSTEM / CurrentControlset / Services
3. Open msahci
4. In the right field left click on "start" and go to Modify
5. In the value Data field enter "0" and click "ok"
6. exit "Regedit"
7. Reboot Rig and enter BIOS (typically hold "Delete" key while Booting)

In your BIOS select "Integrated Peripherals" and OnChip PATA/SATA Devices. Now change SATA Mode from IDE to AHCI.

You now boot into Windows 7 or Vista, and the OS will recognize AHCI and install the devices. Now the system needs one more reboot and voilla... enjoy the improved SSD performance.
Click to expand...

Here's the document I follow from guru3d,I was surprised though as its a little outdated when using with the latest versions of windows 7 as most of the options are pre disabled/set when windows 7 detects an SSD.

DavidGP · Mar 24, 2012

Hi dlb

noooo no need for defrag, indexing etc with an SSD, and in Windows 7 if you do a new clean install with that OS those items shoudl be disabled by default, I know they where when I installed my SSDs.

Also no need for System Restore also, just clone/image your SSD with a good backup app (Acronis/Easyus) periodically.

If you Raid them then TRIM is disabled as upto now they have not added TRIM for raid, but then I have not read up on the latest SSDs with newer controllers, the Sandforce controllers do have a garbage collection function that I believe works in Raid, seems to work ok on mine, as they have no degraded at all in performance in nearly a year.

shnerdly · Mar 24, 2012

Someone should make a sticky out of the info Rikky posted. It's a very concise guide to using SSD's without being 10 pages long.

Awesome post Rikky, thanks for investing the time.

dlb · Mar 24, 2012

Awesome info! Thanks to all!

I freekin' LOVE the MG forums... they have the BEST members.

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SSD and defrag - question

dlb MajorGeek

cabbiinc Staff Sergeant

plodr MajorGeek Super Extraordinaire Moderator Staff Member

Rikky Wile E. Coyote - One of a kind

DavidGP MajorGeeks Forum Administrator - Grand Pooh-Bah Staff Member

shnerdly MajorGeek

dlb MajorGeek