Wouldn't a defrag make it easier to reconstruct data in a loss scenario where 
you're (geeze I can't think of the name, finding files by structure).
Inb4backup

Daniel Wolf

From: [email protected] [mailto:[email protected]] On 
Behalf Of James Button
Sent: Monday, May 19, 2014 2:40 PM
To: [email protected]
Subject: RE: [NTSysADM] Defrag and SSD's

Remember that a SSD is a cluster of storage cells that the management program 
in the SSD maps to the drive image that the OS driver sees.

Defragging the drive from the PC OS does not physically sequence the data in 
those cells, it causes the storage management facility on the drive itself to 
go through the (to it) arduous process of copying cells of data to other cells, 
adjusting the physical to logical map,  and then erasing the data from the cell 
'cleared'
Erasure and writing may possibly take 4 times as long as a read, and actually 
reduces the life of the 'erased' data storage cell as well as the storage used 
for the physical to logical map.

Defrag  originally had a triple benefit:

Avoid head movement delays while disparate parts of the file were read -
Does not apply to SSD's

Avoid extra reads of the space allocation table required to assemble a list of 
the locations of the data on the drive -
Not particularly relevant on drives with large cache, and systems with 
gigabytes of real memory

Collect the FAT directory entries into a single block of storage of the drive 
(usually ordered, and clustered with other directory lists) -
Certainly does not apply under NTFS  where all the entries are assembled as 
detailed by MS and according to the space available within the MFT, and the 
file's creation full name.
And I have been told that Windows will do some compression/tidy up work on the 
MFT as a background task


So - I'd say defrag of a SSD is actually more likely to cause the system to be 
slower, than to be faster!

But then again, that's only my understanding!

JimB






From: [email protected]<mailto:[email protected]> 
[mailto:[email protected]] On Behalf Of Micheal Espinola Jr
Sent: Monday, May 19, 2014 8:00 PM
To: ntsysadm
Subject: Re: [NTSysADM] Defrag and SSD's

Its never been a question if fragmentation happens on an SSD. It does. The 
question is whether or not its worth de-fragmenting:

  1.  Are you getting a worthwhile performance gain?
  2.  Is the effort required deteriorating ROI due to user interference or 
shortened MTF in a cost-prohibitive manner?

Everything I have read indicates that it significantly hurts the MTF, and the 
performance gain is negligible.  ROI of course can vary greatly depending on 
what you are doing with the equipment, and what that means to you fiscally.  
So, it is possible that defrag'ing an SSD is a worthwhile investment.

I would imagine that is something akin to the way [fraudulent] investors short 
the stock market by paying for their analytical servers to be physically closer 
to the Exchange's servers.  Thus gaining micro-seconds of advantage for every 
trade.

--
Espi


On Mon, May 19, 2014 at 11:42 AM, Dave Lum 
<[email protected]<mailto:[email protected]>> wrote:
Truth, or salesmanship?
http://www.condusiv.com/knowledge-center/videos/videos.aspx?index=13

I wonder if the actual productivity increase would more than pay for the
product.

Dave "skeptical"



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