Solved

Harddisk Problem

Posted on 2004-09-01
5
350 Views
Last Modified: 2010-04-25
Hi, my harddisk as acting quite weirdly these days. I have a 120gb Samsung 1203N harddrive. I have 4 partitions on it. All the partitions are FAT32. One of the partition is giving me problems. Every time i remove some files from that partition, it doesnt free's the removed amount. i.e if i remove a 700 mb file, then it shows that i have only removed 400-500 mb. It happens all the time now. I ran the Bad sector test, and it didnt showed any errors. I have defragmented this partition but even after that i m having the same problem. Plz help me out guys. The harddisk is only 15 months old.
0
Comment
Question by:nitwit09
5 Comments
 
LVL 57

Expert Comment

by:Pete Long
ID: 11950552
this sounds normal - be aware of the difference between file siza and "size on disk"

Size Vs Size on Disk

Size refers to the files actual byte count. Size on disk refers to the amount of cluster allocation the file is taking up.

Drives are organized by fixed-size units called clusters. The size of a cluster depends on several factors, the most crucial being file system and partition size.

Some background to help you understand:
Back in the days of DOS and Win95, the only usuable file system was FAT16 (also known as FAT). Because hard drives were so small back then (1GB was considered HUGE), FAT's limitations were minor, one of which was the limitation that the maximum partition size was 2GB.
With FAT16, the cluster size within a partition was determined by the size of the partition. Here is a chart showing the default cluster size for various FAT16 partition sizes:

Drive Size FAT Type Sectors Cluster
(logical volume) Per Cluster Size
----------------- -------- ----------- -------
0 MB - 15 MB 12-bit 8 4K
16 MB - 127 MB 16-bit 4 2K
128 MB - 255 MB 16-bit 8 4K
256 MB - 511 MB 16-bit 16 8K
512 MB - 1023 MB 16-bit 32 16K
1024 MB - 2048 MB 16-bit 64 32K

Now, with small drives, this wasn't a problem because partitions were small. Once drives started growing, the cluster size issue became problematic.

Here's why:
When you write a file to disk, the smallest unit it can take up is 1 cluster. If you have a 1024MB (1GB) partition, and the default cluster size is 32KB, a 1KB file will take up a 16k cluster.
Since you can't have more than one file occupying a cluster, the remainder of that cluster is considered wasted space. In this example, a 1KB file is taking up 32KB of disk space, and wasting 31KB of that space.
Say you have a 68KB file. That file will be written acrosss several clusters, since a cluster is smaller than the actual file. Thus, a 68KB file will take up 2 full 32KB clusters, and 4KB of a third cluster, while also wasting 28KB of that third cluster. While the file is only 68KB, it's taking up 96KB of disk space.

As you can see, with a lot of small files, you can waste a ton of space on such a drive.

To remedy the situation, MS unveiled FAT32 with the introduction of Windows 98. FAT32 not only allowed for significantly larger partition sizes, but also reduced the default cluster size dramatically. Under FAT16, a 2GB partition used a default cluster size of 64KB. Under FAT32, that was reduced to 4KB. A 16GB partition only used 8KB clusters, and up to 32GB uses only 16KB clusters.
As you can see, the savings on such large drives can be significant, resulting in more usuable drive space.

With Windows XP, the home user was introduced to NTFS. Under NTFS, a 1GB partition uses 2KB clusters, and anything above that up to 2TB (terabytes) only uses 4KB clusters.

So, the reason you're seeing that difference is because when you select properties, the Space On Disk reading is accounting for the wasted space attributable to the cluster size on the disk.

Note: MS has a chart with the cluster sizes listed on TechNet (http://www.microsoft.com/technet/treeview/default.asp?url=/TechNet/prodtechnol/winxppro/reskit/prkc_fil_lxty.asp).
Ref: http://forums.aliensoup.com/archive/index.php/t-6985
0
 

Author Comment

by:nitwit09
ID: 11951051
But how come this thing started suddenly. Before, if i was moving a 700mb or 1gb movie, then i use to get same amount. But not any more.
0
 
LVL 45

Expert Comment

by:patrickab
ID: 11951556
Have you checked it out with a DOS command eg enter first COMMAND in the Run dialogue box, press enter and then enter the drive letter as for example C: and press enter, after that enter DIR and press enter. To exit the DOS dialogue box enter EXIT at the prompt and press enter. The DIR command will list everything on the drive and the total space taken up by it. It's crude but it will ensure that the Windows software is reporting what's going on correctly.
0
 
LVL 69

Accepted Solution

by:
Callandor earned 150 total points
ID: 11951919
Have you emptied out the recycle bin, and any special protected recycle bins (if you're using Norton)?
0
 

Author Comment

by:nitwit09
ID: 11952333
hi callondor, its working now. Something was wrong with Norton Protected files. It was not deleting the files properly. So, i had to delete it manully.
0

Featured Post

How your wiki can always stay up-to-date

Quip doubles as a “living” wiki and a project management tool that evolves with your organization. As you finish projects in Quip, the work remains, easily accessible to all team members, new and old.
- Increase transparency
- Onboard new hires faster
- Access from mobile/offline

Join & Write a Comment

Suggested Solutions

Many people don't really know what the difference is between memory and storage. And most regular users don't understand the relationship between any of those fancy words printed on the front of their new computer. Of course, it's perfectly fine -- …
Like many organizations, your foray into cloud computing may have started with an ancillary or security service, like email spam and virus protection. For some, the first or second step into the cloud was moving email off-premise. For others, a clou…
Illustrator's Shape Builder tool will let you combine shapes visually and interactively. This video shows the Mac version, but the tool works the same way in Windows. To follow along with this video, you can draw your own shapes or download the file…
Polish reports in Access so they look terrific. Take yourself to another level. Equations, Back Color, Alternate Back Color. Write easy VBA Code. Tighten space to use less pages. Launch report from a menu, considering criteria only when it is filled…

744 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

9 Experts available now in Live!

Get 1:1 Help Now