size on disk

[Guest]

Sometimes the "size on disk" of a file is much larger than the "size" of the
file. How can that be avoided? In other words, what should be done so the
"size on disk" is about the same as the "size"?

 

[Bruce Chambers]

Sometimes the "size on disk" of a file is much larger than the "size" of the
file. How can that be avoided? In other words, what should be done so the
"size on disk" is about the same as the "size"?

There's very little that can be done about it, unless you've some way
to ensure that each file's size is an even multiple of the partition's
cluster size.

"Size" refers to the actual total of the sizes of all of the
individual file sizes, while "Size on Disk" refers to the total amount
of disk space occupied by those files. The difference is because some
of the files do not occupy an entire cluster. For instance, a 1 Kb file
is occupying a single 4 Kb (or 8 Kb or 16 KB) cluster. Clusters cannot
be shared by different files, so there will always be some wasted space
whenever a file doesn't completely fill a cluster. If there are a lot
of small files, the wastage becomes quite noticeable.


--

Bruce Chambers

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[Rick Rogers]

Hi,

Depends on the actual size of the file and the default cluster size of the
file system. In NTFS, the default is 4k clusters, so a 2.5k file will still
occupy a 4k space. Large files are spread across different clusters in a
volume, and each part may not entirely fill a cluster, so there will always
be some space left unused.

--
Best of Luck,

Rick Rogers, aka "Nutcase" - Microsoft MVP

Windows help - www.rickrogers.org
My thoughts http://rick-mvp.blogspot.com

 

[Ken Blake, MVP]

Sometimes the "size on disk" of a file is much larger than the "size" of the
file. How can that be avoided? In other words, what should be done so the
"size on disk" is about the same as the "size"?

Answered in another newsgroup. Please do not send the same message
separately to more than one newsgroup (called multiposting). Doing so
just fragments the thread, so someone who answers in one newsgroup
doesn't get to see answers from others in another newsgroup. And for
those who read all the newsgroups the message is multiposted to, they
see the message multiple times instead of once (they would see it only
once if you correctly crossposted instead). This wastes everyone's
time, and gets you poorer help than you should get.

If you must send the same message to more than one newsgroup, please
do so by crossposting (but only to a *few* related newsgroups).

Please see "What is the accepted way to share a message across
multiple newsgroups?" at http://smjg.port5.com/faqs/usenet/xpost.html

 

[b11_]

Ken: the link you posted is outdated. Try it.
___________________________________________________________

 

[Ken Blake, MVP]

Ken: the link you posted is outdated. Try it.

Yes, I see that it is. Thanks for pointing it out.