[comp.sys.hp] X11 R$ performance

hearn@randvax.UUCP (Tony Hearn) (03/02/91)

We are currently running X11 R4 (from hpcvaaz) on an HP 835 and are having
performance problems.  The longer a single program communicates with a
window, the poorer the performance.  This appears to be true for all
applications.  The same appears to be true on the HP 300's.  For example,
to run xdvi on a 140k byte dvi file takes the following amount of time:


HP 835           184 seconds
HP 370           140 seconds
SPARCStation      15 seconds

What's most irritating is that the first page on the HP's really flies by
and then it runs slower and slower.  To isolate the problem, I ran xdvi on
a SUN 4/260 with output on the HP's:

SUN 4/260 -> HP 835     18 seconds   
SUN 4/260 -> HP 370     26 seconds

So it's evidently not the server's fault, rather its Xlib's problem.
Has anyone else seen this problem? Are there any simple fixes?

Thanks,
Tony Hearn

PS:  We are still running an old libX11.a, since the one from hpcvaaz is
not compatible:

-r--r--r--   1 bin      bin       481540 Oct 12  1989 /fermat/usr/lib/libX11.a

harry@hpcvlx.cv.hp.com (Harry Phinney) (03/07/91)

Tony Hearn writes:
> The longer a single program communicates with a
> window, the poorer the performance.  This appears to be true for all
> applications.

I can believe this is true for some (likely buggy) applications, but I
do not believe it is true for all applications.  I have hpterms which I
run all day.  They do not slow down.  I have several HP-VUE programs
which I run all day.  They do not slow down.  These are linked with the
same libX11.a which we ship with HP-UX, so I doubt there's a widespread
problem, but I could be wrong.

> So it's evidently not the server's fault, rather its Xlib's problem.
> Has anyone else seen this problem? Are there any simple fixes?

Do you know if "xdvi"'s data space grows suspiciously as it slows down?
I have seen programs which fail to dispatch/dispose of all the events
which they receive.  This causes xlib to allocate memory to hold these
events.  What malloc are you linking into the program?  Are you linking
xdvi with libmalloc.a, or are you relying on the malloc in libc.a?

> PS:  We are still running an old libX11.a, since the one from hpcvaaz is
> not compatible:

> -r--r--r--   1 bin      bin       481540 Oct 12  1989 /fermat/usr/lib/libX11.a

So you're still running HP-UX 6.5.  I don't remember any significant
xlib bugs in 6.5, but my memory _could_ be failing :-).  The 6.5 xlib is
based on the R2 release of X11, while the HP-UX 7.0 version is R3, and
the one you got from hpcvaaz is based on R4.  I presume the
incompatibility you are encountering is due to library/compiler changes
between the 6.x and 7.x releases.  Is there any chance of updating your
system to 7.0 and re-testing?

Harry Phinney   harry@hp-pcd.cv.hp.com