mssing memory on hard disc
Thread Starter
Joined: Sep 1999
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From: ask crewing i dont know
mssing memory on hard disc
My computer has started to go very slow. if i do a properties check of drive c it shows 652mb free on a 10gb disc (thats drive c the boot up one with xp but not a lot installed on it - i use the sata with xp 64 on for most things - aol broadband wont work on xp64). if i open drive c folder select all including hidden file an a properties checek - its come to 6.4 gb. so where is the missing 3gb ?? how can i free it up short of that old favourite format c an reinstall ?
Joined: Jan 2002
Posts: 156
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From: Sandwich, Kent, UK
Hi LDG,
The two things you've done are showing you two different things - the amount of free disk space, and the total size of all your files. The two things will never quite add up to the size of your disk. Space on your disk is allocated in 'clusters', and each file always uses a whole number of clusters - any unused space in the last cluster becomes unavailable for any other purpose. The cluster size of modern disks is quite large, probably around 32Kb. So, if you have 1000 files, each of size 10 bytes, their total file size is 10,000 bytes (approx 10Kb), but the will use up 32,000Kb (approx 32Mb) of disk space.
If you happen to have a lot of small files on your disk (possibly cookies, cached internet files, etc), you can waste a lot of disk space like that. Smaller clusters are more efficient, but make your file system slower.
Additionally, not all the space on a 10Gb disk is available for files - a not insignificant proportion is used up with the File Allocation Table (or whatever the equivalent is under NTFS), folder information, etc etc.
On a slightly pedantic note, disk space is not the same as memory. Memory and disk space are two different types of storage. It's good to get the terminology right - if you phone a PC engineer and say you're running out of memory, s/he will assume you mean RAM, not disk space.
:-)
The two things you've done are showing you two different things - the amount of free disk space, and the total size of all your files. The two things will never quite add up to the size of your disk. Space on your disk is allocated in 'clusters', and each file always uses a whole number of clusters - any unused space in the last cluster becomes unavailable for any other purpose. The cluster size of modern disks is quite large, probably around 32Kb. So, if you have 1000 files, each of size 10 bytes, their total file size is 10,000 bytes (approx 10Kb), but the will use up 32,000Kb (approx 32Mb) of disk space.
If you happen to have a lot of small files on your disk (possibly cookies, cached internet files, etc), you can waste a lot of disk space like that. Smaller clusters are more efficient, but make your file system slower.
Additionally, not all the space on a 10Gb disk is available for files - a not insignificant proportion is used up with the File Allocation Table (or whatever the equivalent is under NTFS), folder information, etc etc.
On a slightly pedantic note, disk space is not the same as memory. Memory and disk space are two different types of storage. It's good to get the terminology right - if you phone a PC engineer and say you're running out of memory, s/he will assume you mean RAM, not disk space.
:-)
