It’s been written about everywhere, but since we keep spotting installations in the wild where people don’t know about it, it probably deserves another mention.
By default, Linux uses the atime option on a disk mount, which means it writes a timestamp (e.g. a write to the drive) every time it reads anything. So in this case, reads cause writes – and also disk seeks, because a read from a file will then trigger having to write to the directory that contains the file. This even occurs if a file is read from the file system’s page cache (reading from the machine’s memory rather than the drive).
Unless you require an audit trail of users …[Read more...]