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I/O efficiency question
I have an Allegro 4.1 program (running on a Sun Sparcstation-II) which
does file i/o with large files (over a megabyte). I am trying to optimize
the file i/o and noticed that 'read-char' and 'write-char' are fairly
slow, the reason being that they first call for example:
and then: stream:stream-read-char.
When I tried calling stream:stream-read-char directly, it went faster
but still tried invoking the (METHOD STREAM:STREAM-READ-CHAR ...).
By calling EXCL::STM-FILE-BUFFERED-READ-CHAR and
EXCL::STM-FILE-BUFFERED-WRITE-CHAR directly I was able to bypass
the method stuff, speeding up my program considerably (45%).
I would rather not call internal Allegro functions, but I can't seem
to find a way around this. I tried putting a
(declare (type STREAM:FUNDAMENTAL-CHARACTER-INPUT-STREAM stream)) and
(declare (optimize (speed 3) (safety 0) (debug 0)))
in my read/write functions, but this didn't seem to help.
So my question is, is there a more elagent way to do this, and if not,
why not make the compiler bypass the method stuff for read-char and write-char
if it knows that the type is a character stream?
Pete Shell email@example.com