optimal buffer size for writing to harddisks ?

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Article #2258

#2258

From: Skybuck Flying
Date: Sat, 21 Sep 2002 13:36

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Hi...

Do you happen to know what would be the optimal buffer size for writing to
harddisks ?

It probably differs from disk to disk... probably even os to os... but I am
talking windows here.

For example a buffer of 1 byte would be very slow. Writing and reading to
harddisks/files byte by byte is very slow... probably a mixture of seektime
but probably not because of cache... the reason it's slow is probably api
calling etc...

Also a buffer of 10 or 100 megabyte seems to slow also... it's just too
big...

So what would be the optimal buffer size for TfileStream.Write... ?

I once used a 4 kb buffer which worked ok...

Is there any theory on this ? :)

Skybuck.

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Subject: optimal buffer size for writing to harddisks ?
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