Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!purdue!decwrl!decvax!crltrx!max.crl.dec.com!jg
From: jg@max.crl.dec.com (Jim Gettys)
Newsgroups: comp.windows.x
Subject: Re: DEC3100-Xlib performance
Message-ID: <173@crltrx.crl.dec.com>
Date: 19 May 89 18:25:05 GMT
References: <2451@shlump.dec.com> <1201@ttds.UUCP>
Sender: news@crltrx.crl.dec.com
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I am responding, as Joel McCormack's building is having network trouble.

BTW, it is the server, not the library....

The R3 arc code, as originally distributed, is EXTREMELY slow.  For the first
time, it matched the specification. Unfortunately, the specification
as written is very difficult to implement correctly (we did not realize this
at the time it was written.  Sigh....). PMAX 
(DECstation 3100) is using an R3 based server.  We did not realize how slow
the arc code was at the time, or we would have done something about it....

Since R3 first came out, there have been improvements in the code to the
point where it is merely slow; it will be at least 3x faster in the next
release (Ultrix 3.1, UWS 2.1), according to the performance data I have.
More work needs to be done yet.

BTW, most graphics operations in the next release on the color display
will be very much faster than the first release, in which only text, line 
drawing and basic raster operations had been optimized.  Factors of two or
more improvements in other graphics areas are common; even the items which Joel
had had time to optimize for the first release are faster yet.
				Jim Gettys
				Cambridge Research Laboratory
				Digital Equipment Corporation