Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!tut.cis.ohio-state.edu!ucsd!cacilj!paul
From: paul@cacilj.UUCP (Paul Close)
Newsgroups: comp.windows.x
Subject: How can I evaluate the performance/efficiency of my X program?
Message-ID: <1377@cacilj.UUCP>
Date: 2 Feb 90 00:26:34 GMT
Reply-To: paul@cacilj.UUCP (Paul Close)
Organization: CACI Products Company, La Jolla, CA
Lines: 40

I have a graphics library which uses Xlib calls to do its work.  The programs
linked with this library run slower than the equivalent program run on
SunView.  I would expect some overhead due to communication between server and
client, but I would like to examine the issue of performance/efficiency.

I started by building a profiled version of Xlib.  Unfortunately, most of the
real work is being done by the server, as evidenced by the cpu time (around 5%
utilized!).  My profiled output at least tells me how many calls I am making.
Is there some way to figure out how much time each Xlib call is really taking?

My application involves animation, so there is a lot of polling, a lot of
clipping, and a lot of drawing.  Using the profiler, I found that some of
the following calls are called the most (roughly in order):

	XPending	(I have to poll for events)
	_XGenerateGCList
	_XFlushGCCache
	XDrawLines
	XSetForeground
	XSetClipRectangles
	XCopyArea
	XFillRectangle
	XFillPolygon
	XSetLineAttributes
	XSetFillStyle
	XSetDashes
	XAllocColor

Is the high activity in _XGenerateGCList and _XFlushGCCache indicate that I am
not using GCs effectively?  I only have two GCs per window, and generally use
calls like XSetForeground to set the drawing color before drawing part of an
object.  In fact, the three routines _XGenerateGCList, _XFlushGCCache, and
XSetForeground all have roughly the same number of calls and are near or at
the top of the list.

Anyone care to comment?
-- 
Paul Close	paul@cacilj.CTS.COM 	...!{uunet, ucsd, crash}!cacilj!paul

    The Obi-wan Kenobi method:  "Use the Source, Luke"	-Jim Fulton