On Fri, 30 Jul 2004, ger wrote:
> From man mount page
> sync All I/O to the file system should be done synchronously.
>> To me this means that all I/O operations occur at the same time. This
No. It means that I/O is done at the time you ask. Asynchronous means
you ask for the I/O to be done, and then you go away again, and the IO
happens at some later time.
> opposite. I cannot see how this option in mount will prevent or reduce data
> loss from unexpected disconnections during write operations.
It won't reduce the data loss, it reduces the chance of data loss - the
window of opportunity is smaller.
Synchronous is "slower" because a) the writing application is locked up
for the duration and b) every write goes through to the device in this
way, whereas in the asynchronous case, the application might
modify the same part of the file multiple times before the device driver
got to it, in which case it is written only once.
Maintained by the ILUG website team. The aim of Linux.ie is to
support and help commercial and private users of Linux in Ireland. You can
display ILUG news in your own webpages, read backend
information to find out how. Networking services kindly provided by HEAnet, server kindly donated by
Dell. Linux is a trademark of Linus Torvalds,
used with permission. No penguins were harmed in the production or maintenance
of this highly praised website. Looking for the
Indian Linux Users' Group? Try here. If you've read all this and aren't a lawyer: you should be!