Defragging on SSDs?

[Goldfish4209]

Since there's virtually no access time on SSDs, doesn't that make defragging redundant? Also, wouldn't the limited lifespan of SSDs make an even greater disincentive against defragging?

 

[taltamir]

there is no point to even defrag a platter drive. Defragging takes hours, lowers the drives lifespan, and costs money (electricity, for the extra CPU cycles and HDD activity, check your power draw from the wall at idle and load).
While the HDD is defragging you experience severe slowdowns and inability to use the system.
And what does it give you? slightly faster sequential read speeds?
A file server that servers thosands of people the exact same file over and over should be defragged (or better yet, should use a ram drive), but there is no reason to EVER defrag a home drive.

The SSD its even worse, it does not give you increased access speed, and SSDs rely on special algorithms to intentionally fragment files in a way that increases their lifespan (Since each individual sector has a limited amount of writes before it fails).

the only "real" benefit of defragging is that can it recover insignificant amounts of space if a file takes only parts of sectors instead of whole sectors. Still, not a good justification.

 

[octopus41092]

Pointless on SSD's since theres practically no access time you'd only improve your access time by nanoseconds, but I have to say it isn't always useless on a home drive. At a certain point the metadata will get really fragmented and by defragging it you increase your boot up times by a lot. You could argue that it's boot up time doesn't really matter anyways but to some people it does. Also, it can speed up the overall "snappiness" of your system when you defrag. Sure, you don't have to do it really often, maybe once every couple months, hell even once a year. But I would still say that its worth it to defrag on a standard hard drive.

 

[Modelworks]

Defrag of SSD would shorten the lifespan considerably. But it is not pointless on platters. How often it needs to be done depends on the system. If you never delete anything you would never need to defrag. But if you install and delete often it will increase the fragmentation more and more.

 

[Modelworks]

Originally posted by: taltamir

A file server that servers thosands of people the exact same file over and over should be defragged (or better yet, should use a ram drive), but there is no reason to EVER defrag a home drive.

Copy a file into 800 fragments scattered around the drive then measure the time to copy them compared to a contiguous file. You can't get away from the facts that it takes even the fastest drive time to move the head to a new sector. Seek time is low, but it is not instant.

 

[supremelaw]

I think an occasional DEFRAG of the C: system partition definitely
results in shorter "strokes" of the read/write armature.

This is also one of the reasons why I recommend that new users
partition a single Raptor first into a 20-30GB C: and the rest as
a different drive letter -- for storage of data like drive image files.

Then, after writing OS files into C:, defragging it at that point
ends up "packing" all files into the lowest numbered sectors
in that partition -- read "outermost cylinders" where head seeks
are minimal ("outer" means away from the spindle axis;
"inner" means closer to the spindle axis).

That, in turn, results in "short strokes" whenever the read/write
armature must access the C: partition for any reason:
even if the armature must travel to the innermost cylinder of C:,
that cylinder is MUCH CLOSER to the outermost cylinder
than is the innermost cylinder on each platter, PROVIDED
that C: stays relatively small e.g. 20-30GB on a 150GB HDD.

I've installed XP/Pro x32 on a 10GB C: partition, and it fits.

VISTA is another story, however.

Morale of this message: PLAN AHEAD!


Sincerely yours,
/s/ Paul Andrew Mitchell, Inventor and
Webmaster, Supreme Law Library

All Rights Reserved without Prejudice


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-Schadenfroh (AT Mod)

 

[supremelaw]

One more thing: I haven't confirmed this for sure,
but I would expect MS DEFRAG to re-allocate the swap file
along sequential sectors: that swap file may NOT be
allocated along sequential sectors if its size has been
changed by the User, for example.

The better defraggers support priority setting by file and folder name:
higher priority files get moved to lower-numbered sectors within a partition,
resulting in shorter strokes of the read/write armature after C: is defragged.

The swap file can also be moved entirely to a RAMDISK (where defragging is irrelevant),
using software products like RamDisk Plus from www.superspeed.com .

The very latest release of RamDisk Plus (reportedly in Beta for 2 more weeks),
permits creation of a RAMDISK in RAM that remains "unmanaged" by Windows.

This would be a good reason to "bulk up" on RAM, even if you are using XP x32.


p.s. I notice that PAE (Physical Address Extension) has been enabled on our
XP x32 production workstation: I traced this to a default when DEP is enabled:
in Startup and Recovery: /noexecute=optin .

Get there as follows:

My Computer | Properties | Advanced | Startup and Recovery | Settings | System Startup | Edit

-and-

My Computer | Properties | Advanced | Performance | Settings | Data Execution Prevention | Turn on DEP

Be aware, however, that PAE has a troubled history with XP x32,
chiefly due to poorly written device drivers.


Sincerely yours,
/s/ Paul Andrew Mitchell, Inventor and
Webmaster, Supreme Law Library

All Rights Reserved without Prejudice