Re: File output and buffering

[Maciej Sobczak <see.my.homepage@gmail.com>]

On 20 Sie, 17:39, "Dmitry A. Kazakov" <mail...@dmitry-kazakov.de>
wrote:

> Buffering is used to make I/O in an asynchronous and/or conveyered way.

No, it is not asynchronous. Nothing happens in the background, the
operations are only grouped. The group is (usually) transmitted in the
synchronous fashion.

I do not know what is "conveyered".

> That does not make I/O faster in terms of latencies.

It does make it faster in terms of throughput.

Note: I do not imply that throughput is more valuable for optimization
than latency - these can be different goals and usually are.

> Any language buffer on top of numerous layered buffers, typical for an OS,
> adds nothing, but overhead.

It can reduce the overhead that is associated with the number of
requests. System calls are not free and there is also a significant
latency of the medium that is better to be avoided (like network
roundtrips or disk seek times).

--
Maciej Sobczak * www.msobczak.com * www.inspirel.com

Database Access Library for Ada: www.inspirel.com/soci-ada