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

  • Thread starter Thread starter Skybuck Flying
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Skybuck Flying

Guest
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.
 
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.
>
>
 
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
 
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
 
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.
> >
> >
>
>
 
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.
>>
>>
>
>
 
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