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Subject: Re: Regarding IO to disk
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Jawahar Tadipatri wrote:
> Hi Folks,Can anyone please let me know the average/typical time taken for
> completing one IO operation (read and write) to disk?
> More specifically, time taken for writing a string to a file.

Your question is incomplete and cannot be answered correctly.

Declared average latency for desktop hard drives (see 
http://www.seagate.com/docs/pdf/datasheet/disc/ds_barracuda_7200_12.pdf) 
is about 4 ms. Real performance depends on about a dozen factors.

See here: http://www.google.com/search?q=hard+drive+performance for more 
information.