cu on a 3b1 is SLOW

root at spdyne.UUCP root at spdyne.UUCP
Wed Aug 2 01:30:23 AEST 1989


In article <18818 at mimsy.UUCP>, steveg at tove.umd.edu (Steve Green) writes:
> 
>  I am a new unixpc user, but it seems that when I do a cu to another unix
>  machine at 9600 baud (a Mac II) it moves like molasses.

Written  by stevens at hsi.UUCP
> The first problem is that cu does a read() system call of 1 byte from
> the communications line, followed by a write() of 1 byte to the standard

    I don't think that this is the major problem.....

> The second problem is that the 3b1 console can't run at 9600.
> Cat a big file to the screen and time it - it's about 5500 baud max.

    Which is not all that bad, considering it's running in Graphics
mode!  On a PC all you have to do is to put 1 byte in 1 location in memory.
On the 7300, I belive you would have to update at least 14 bytes.  This would
make it about 14 times slower.  (Assuming a 14x8 char set, But I think that
it is a 14x9, thus one would have to *modify* (read then write) 28 bytes.
As well as do a bunch of And's & Xor's.. )  This could make it about
about 60 times slower -- Just because it's in graphics mode...  The
Mac had the same problem when it first came out.. (as I recall..)

    And scrolling you have to move the entire graphics image.


    Chert Pellett
    root at spdyne

PS: I'm not knocking the 7300/3b1... I like being in Graphics mode... I
was raised on PLATO.... (And GIGI's on VMS...)



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