Jump to content

NTFS uses least used clusters ? (Cluster durability/lifetime ?)


Recommended Posts

Guest Skybuck Flying
Posted

Hello,

 

Somebody believes NTFS works as follows:

 

When NTFS needs to write new data to the disk it finds the clusters which

have been least used.

 

This would ensure longer disk life.

 

If NTFS simply re-used the same clusters over and over and over again this

would lead to early drive failure (???).

 

Is there any thruth in this or is this internet/usenet myth ? Me wonders...

 

(It does so via a list of clusters somebody said.)

 

(Freeed clusters would be added to the back of the list)

(Needed clusters would be removed from the front of the list)

 

Thus this would automatically cycle the clusters somewhat.

 

Sounds plausible.

 

Bye,

Skybuck.

  • Replies 5
  • Created
  • Last Reply
Guest Tony Sperling
Posted

Re: NTFS uses least used clusters ? (Cluster durability/lifetime ?)

 

This has to be a misconception turned 'myth'. The used/unused clusters are

magnetic particles that are actually kept alive by use - if not periodically

revived by rewrites, they will fade.

 

The HD head arrangements are worn out by use, and fragmentation aggregates

movement!

 

If I remember, NTFS is designed to use the smallest free space available for

writing new data to disk. Microsoft has actually fostered it's own 'myth',

in saying the Filesystem isn't likely to fragment as much as FAT. In

reallity NTFS is happier fragmenting than not, but it's design is such that

it doesn't care (performancewise) if it is fragmented or not, until it

becomes nearly full, then it grinds to a halt. There are, however,

filesystems around that really doesn't fragment as much, and therefore also

doesn't lose performance as a result of that. But NTFS doesn't care!

 

NTFS, primarily, is a SAFE filesystem, and it is miles ahead of FAT. It my

not be the best, but the 'best' is really allways determined by the user's

personal needs!

 

 

Tony. . .

 

 

"Skybuck Flying" <spam@hotmail.com> wrote in message

news:848d1$47db3243$541983fa$23029@cache3.tilbu1.nb.home.nl...

> Hello,

>

> Somebody believes NTFS works as follows:

>

> When NTFS needs to write new data to the disk it finds the clusters which

> have been least used.

>

> This would ensure longer disk life.

>

> If NTFS simply re-used the same clusters over and over and over again this

> would lead to early drive failure (???).

>

> Is there any thruth in this or is this internet/usenet myth ? Me

wonders...

>

> (It does so via a list of clusters somebody said.)

>

> (Freeed clusters would be added to the back of the list)

> (Needed clusters would be removed from the front of the list)

>

> Thus this would automatically cycle the clusters somewhat.

>

> Sounds plausible.

>

> Bye,

> Skybuck.

>

>

Guest Maxim S. Shatskih
Posted

Re: NTFS uses least used clusters ? (Cluster durability/lifetime ?)

 

> When NTFS needs to write new data to the disk it finds the clusters which

> have been least used.

 

From what I know, both NTFS and FAT use the circular allocation from the hint

value, which is initially just after the last allocated block and then advances

and wraps around the volume end during the mounted volume lifetime.

> This would ensure longer disk life.

 

Looks like lesser fragmentation is more important.

> If NTFS simply re-used the same clusters over and over and over again this

> would lead to early drive failure (???).

 

Yes, really ???

> Is there any thruth in this or is this internet/usenet myth ? Me wonders...

 

Looks like a myth.

> (It does so via a list of clusters somebody said.)

 

There are no lists of free clusters in FAT and NTFS, only the bitmap.

 

NTFS keeps the bitmap on disk, while FAT builds it in memory from the on-disk

FAT table, with FAT12/16, this is done once at mount time, with FAT32, this is

done chunk-by-chunk in runtime.

 

--

Maxim Shatskih, Windows DDK MVP

StorageCraft Corporation

maxim@storagecraft.com

http://www.storagecraft.com

Guest Maxim S. Shatskih
Posted

Re: NTFS uses least used clusters ? (Cluster durability/lifetime ?)

 

> NTFS, primarily, is a SAFE filesystem, and it is miles ahead of FAT.

 

It's one of the world's oldest logging filesystems, which predates all open

source analogs and most UNIX logging filesystems (except the Veritas's ones).

 

--

Maxim Shatskih, Windows DDK MVP

StorageCraft Corporation

maxim@storagecraft.com

http://www.storagecraft.com

Guest Tony Sperling
Posted

Re: NTFS uses least used clusters ? (Cluster durability/lifetime ?)

 

The wiki, as allways:

 

http://en.wikipedia.org/wiki/NTFS

 

has valuable info.

 

 

Tony. . .

 

 

 

 

 

"Tony Sperling" <tony.sperling@dbREMOVEmail.dk> wrote in message

news:eaD8kfnhIHA.1208@TK2MSFTNGP05.phx.gbl...

> This has to be a misconception turned 'myth'. The used/unused clusters are

> magnetic particles that are actually kept alive by use - if not

periodically

> revived by rewrites, they will fade.

>

> The HD head arrangements are worn out by use, and fragmentation aggregates

> movement!

>

> If I remember, NTFS is designed to use the smallest free space available

for

> writing new data to disk. Microsoft has actually fostered it's own 'myth',

> in saying the Filesystem isn't likely to fragment as much as FAT. In

> reallity NTFS is happier fragmenting than not, but it's design is such

that

> it doesn't care (performancewise) if it is fragmented or not, until it

> becomes nearly full, then it grinds to a halt. There are, however,

> filesystems around that really doesn't fragment as much, and therefore

also

> doesn't lose performance as a result of that. But NTFS doesn't care!

>

> NTFS, primarily, is a SAFE filesystem, and it is miles ahead of FAT. It my

> not be the best, but the 'best' is really allways determined by the user's

> personal needs!

>

>

> Tony. . .

>

>

> "Skybuck Flying" <spam@hotmail.com> wrote in message

> news:848d1$47db3243$541983fa$23029@cache3.tilbu1.nb.home.nl...

> > Hello,

> >

> > Somebody believes NTFS works as follows:

> >

> > When NTFS needs to write new data to the disk it finds the clusters

which

> > have been least used.

> >

> > This would ensure longer disk life.

> >

> > If NTFS simply re-used the same clusters over and over and over again

this

> > would lead to early drive failure (???).

> >

> > Is there any thruth in this or is this internet/usenet myth ? Me

> wonders...

> >

> > (It does so via a list of clusters somebody said.)

> >

> > (Freeed clusters would be added to the back of the list)

> > (Needed clusters would be removed from the front of the list)

> >

> > Thus this would automatically cycle the clusters somewhat.

> >

> > Sounds plausible.

> >

> > Bye,

> > Skybuck.

> >

> >

>

>

Guest Alexander Grigoriev
Posted

Re: NTFS uses least used clusters ? (Cluster durability/lifetime ?)

 

It's not, in general, possible to avoid fragmentation in a generic case.

Even for a single user or writer, it's not generally possible to minimize

fragmentation. When a file is created, there is usually no hint whatsoever

how big it's going to grow. Even though ZwCreateFile can accept initial

allocation size argument, CreateFile doesn't pass it. Thus a particular

strategy to assigning initial place for multiple simultaneously open files

doesn't guarantee that a heavily used disk isn't going to get fragmented.

 

All that fragmentation issue becomes a non-issue, when you have a randomly

accessed database which occupies most of the volume.

 

"Tony Sperling" <tony.sperling@dbREMOVEmail.dk> wrote in message

news:eaD8kfnhIHA.1208@TK2MSFTNGP05.phx.gbl...

> This has to be a misconception turned 'myth'. The used/unused clusters are

> magnetic particles that are actually kept alive by use - if not

> periodically

> revived by rewrites, they will fade.

>

> The HD head arrangements are worn out by use, and fragmentation aggregates

> movement!

>

> If I remember, NTFS is designed to use the smallest free space available

> for

> writing new data to disk. Microsoft has actually fostered it's own 'myth',

> in saying the Filesystem isn't likely to fragment as much as FAT. In

> reallity NTFS is happier fragmenting than not, but it's design is such

> that

> it doesn't care (performancewise) if it is fragmented or not, until it

> becomes nearly full, then it grinds to a halt. There are, however,

> filesystems around that really doesn't fragment as much, and therefore

> also

> doesn't lose performance as a result of that. But NTFS doesn't care!

>

> NTFS, primarily, is a SAFE filesystem, and it is miles ahead of FAT. It my

> not be the best, but the 'best' is really allways determined by the user's

> personal needs!

>

>

> Tony. . .

>

>

> "Skybuck Flying" <spam@hotmail.com> wrote in message

> news:848d1$47db3243$541983fa$23029@cache3.tilbu1.nb.home.nl...

>> Hello,

>>

>> Somebody believes NTFS works as follows:

>>

>> When NTFS needs to write new data to the disk it finds the clusters which

>> have been least used.

>>

>> This would ensure longer disk life.

>>

>> If NTFS simply re-used the same clusters over and over and over again

>> this

>> would lead to early drive failure (???).

>>

>> Is there any thruth in this or is this internet/usenet myth ? Me

> wonders...

>>

>> (It does so via a list of clusters somebody said.)

>>

>> (Freeed clusters would be added to the back of the list)

>> (Needed clusters would be removed from the front of the list)

>>

>> Thus this would automatically cycle the clusters somewhat.

>>

>> Sounds plausible.

>>

>> Bye,

>> Skybuck.

>>

>>

>

>


×
×
  • Create New...