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Blog: SSD

There is a firmware issue on the Crucial M4 drives that can manifest itself during an abnormal shutdown.  When attempting to boot the drive (or access it if it is NOT the boot drive) the bios will tell you during boot that the drive is not accessible. The solution is to to a “Power Cycle” on the SSD. The instructions to do so are found here:  http://forum.crucial.com/t5/Solid-State-Drives-SSD-Knowledge/Why-did-my-SSD-quot-disappear-quot-from-my-system/ta-p/65215

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The procedure is to apply power only to the drive for 20 minutes, remove power for 30 seconds, apply power again for 20 minutes, then the drive magically heals itself.

The real solution is to apply firmware version 040H or later.

Networking, SSD,
 

Crucial M500 SSDs support self-encrypting drive (SED) technology which allows BitLocker for Windows 8 to simply be used for encryption key management rather than software-based encryption.  Out of the box, the drive encrypts all written data and decrypts all read data - and functions like a non-SED drive until key management software like Windows 8 (and Server 2012) BitLocker is used. [more]

When you turn BitLocker on using Windows 8 and a compliant SSD like the M500, you don't have to wait for the whole disk to be rewritten and it's encrypted.  Thus, you can encrypt the whole drive in a couple of minutes or less.  As far as BitLocker and Windows is concerned, it functions just like traditional non-SED drives do regarding pre-boot passwords, recovery keys, etc. 

An interesting spec is Crucial states their SSDs are designed to support 72TB total bytes written (TBW) - which is equal to 40GB per day for 5 years.  It stands to reason that if you don't have to rewrite every byte of an SSD when you use BitLocker to encrypt or decrypt the whole drive, it should help the life expectancy of the drive. 

So, since the drive I/O specs include the hardware encryption overhead, you lose no performance whatsoever when you implement whole disk encryption using BitLocker for Windows 8 on these drives. 

A very basic description of Crucial M500 encryption can be found at

http://forum.crucial.com/t5/Solid-State-Drives-SSD-Knowledge/An-introduction-to-the-encryption-features-of-the-M500/ta-p/128272 

More specs are available (since this is a Micron drive) from:

http://www.micron.com/~/media/Documents/Products/Data%20Sheet/SSD/m500_2_5_ssd.pdf

Networking, Security and Compliance, SSD, Encryption, Windows 8, BitLocker,
 

A while back we blogged about how you should disable the disk defragmentation scheduled task in Windows 7 if you are using solid state drives (SSD).  I would also like to recommend that Superfetch and Prefetch be disabled.  This is done by changing EnableSuperfetch and EnablePrefetcher from 3 to 0 in the registry under HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management\PrefetchParameters.  The Superfetch service should be disabled.

Briefly (and probably a little incorrectly), Prefetch copies frequently accessed files together into a contiguous area on the disk so they can be located and loaded faster.  There is no need to be copying these around – access times are basically the same regardless of where the file is.

Superfetch learns what programs you run when Windows first comes up and gets them loaded into memory before you run them.  In my opinion, the overhead in using this feature outweighs the performance gain, since loading times are so fast with an SSD.  And besides – it’s my own private business what programs I am going to run.

I have read second or third hand that Windows 7 will automatically detect an SSD and disabled these, but depending on the history of your Windows 7 installation, or if it’s a virtual machine, then this might not have happened.  I have also read that if you run the performance troubleshooter, it will may set these values back. [more]

If you want to understand more about Windows 7 and SSDs:

https://blogs.msdn.com/b/e7/archive/2009/05/05/support-and-q-a-for-solid-state-drives-and.aspx

General, SSD, Windows 7,