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china-lee
Contributor
Contributor

关于厚置备置零和延时置零区别

厚置备,快速置零和延时置零区别是什么?

置零的是什么?文件还是空间???

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china-lee
Contributor
Contributor

硬盘置零是什么意思??

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bluefirestorm
Champion
Champion

It is easy to understand the concept of filling with zeroes if you understand the fundamental concepts of computer/OS filesystems.

When a file is deleted, the actual contents are not really deleted (i.e. they are not zeroed out). It only marks the space occupied by the file that was deleted to be available for use. In Windows NTFS, the Master File Table (MFT) is modified but the sectors on the disk is not cleared out. In Linux/Unix systems it would be the inode. That is also why when you delete a 1KB file or a 1GB file, the amount of time is not noticeably different.

As the contents in the storage are not zeroed out, it opens a security risk that a rogue program can be used to snoop/recover the contents of previous files. That is also why when datacenters decommission physical hard disks, they go through a process of writing zeroes and/or degaussing so that the disposed device does not contain any recoverable data.

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