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Re: [LUG] Ensuring data is on disk


Try the " sync " command

On 10/07/2010 21:01, Simon Waters wrote:
Curiosity driven question.

If I write data to my external hard disk, how can I ensure that a read
to verify that data isn't using a cache?

Suddenly I realise that SCSI tape devices simply read the data after
writing it by putting the read head after the write head (if they had
two) thus ensuring your data was on tape in one operation.

The OS caches can be cleared by remounting the device, and there are
other options in later kernels. But I can't find clear documentation for
the behaviour of hard disk caches in such situations.

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