Properties - Size vs Size on Disk

[Kim]

Can anyone tell what the difference is when I take
Properties on a folder, it lists "Size" and "Size on
Disk." The two numbers are different. What does each
stand for?

TIA
Kim

 

[Dave Patrick]

Has to do with 'slack space'. Consider that every file and directory listing
(no matter what size) takes up at least one cluster. Slack space is the area
between the end of the file and the end of the cluster. It can be calculated
roughly by taking 1/2 of the drive's allocation unit (cluster size) times
the number of files, this is the average wasted space. If you have a lot of
small files then the wasted space figure could be larger.

From a command prompt at the root of the drive in question;
chkdsk
to find out your cluster size (allocation unit)

--
Regards,

Dave Patrick ....Please no email replies - reply in newsgroup.
Microsoft Certified Professional
Microsoft MVP [Windows]
http://www.microsoft.com/protect

:
| Can anyone tell what the difference is when I take
| Properties on a folder, it lists "Size" and "Size on
| Disk." The two numbers are different. What does each
| stand for?
|
| TIA
| Kim

 

[John]

Size refers to the actual size of the file. Size on Disk refers to the
amount of storage space that file has used. Files are stored in little boxes
on the disk called clusters. If the an actual file only needs a small part
of the cluster, the unused part of the box will always remain unused however
the Size on Disk for that file will reflect the entire box as being used.

 

[Kim]

Thank you for your quick reply. Very helpful!

 

[Dave Patrick]

You're welcome.

--
Regards,

Dave Patrick ....Please no email replies - reply in newsgroup.
Microsoft Certified Professional
Microsoft MVP [Windows]
http://www.microsoft.com/protect

:
| Thank you for your quick reply. Very helpful!