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description: Messages from Usenet group comp.lang.idl-pvwave, compiled by Paulo Penteado
items: Re: Object graphics under Linux: are they supposed to be that slow?

Re: Object graphics under Linux: are they supposed to be that slow?
type: item
description: Could you post the program? I would like to compare the performance on my machine (PIII 700Mhz, Matrox G400). This way it could be sorted out if its the graphic driver.
creator: marc schellens[1]
date: 2002-01-28T19:33:35-00:00

Re: Object graphics under Linux: are they supposed to be that slow?
type: item
description: Hi Mark: I'm not sure I've the answer for you, but I suspect that the big difference is in the graphics subsystem, the windows more than likely supporting the hardware acceleration and Linux (XFree I'm assuming) not. You didn't mention what version of X you were using. Here's from the XFree site about hardware acceleration support of the latest XFree release: 4.2.0: Support (accelerated) for the Intel i740 is provided by the "i740" driver, and support for the Intel i810 (including i810-dc100 and i810e), i815, and i830 is provided by the "i810" driver. The "i810" driver is currently supported only on Linux and FreeBSD (4.1 and later), and requires AGP GART kernel support. So you might check your kernel and see if it has this compiled in by doing ksyms -m, you should see something about agpgart appear in the output, if you don't you probably need to compile a kernel with support for this. If you do, you might check the output of XFree to verify that it is using the acceleration, if you're kernel supports it. On my system, this is spewed to /var/log/xdm-error.log (I use xdm, you probably do too). My Linux box uses an Nvidia chip and the accelerated-driver is proprietary and buggy, so I've just forgone any acceleration on my system. I don't know what your reasons for moving to Linux were, but if you want accelerated graphics (Open GL / DRI), that's on the bleeding edge of Linux. I've been a Linux user since 1995 and I think it has many advantages, but this is an admitted weakness. I'd be interested to hear what other users say about this, and how well the software accelerated Open GL provided by RSI with IDL for Linux works on other systems. On Mon, 28 Jan 2002 12:23:58 +1300, Mark Hadfield <m.hadfield@niwa.co.nz> wrote: > Hi guys > > I have recently been considering a switch to from Windows to Linux for > various reasons that I won't go into here. I have set up a dual-boot system > on my PC and, as of today I have IDL running on both OSes. I'm afraid it's > been a disa…
creator: nobody@nowhere.com (S
date: 2002-01-28T20:38:07-00:00

Re: Object graphics under Linux: are they supposed to be that slow?
type: item
description: "Steve Smith<steven_smith>" <nobody@nowhere.com> wrote in message news:slrna5be3l.qih.nobody@pooh.nrel.gov... > Hi Mark: > I'm not sure I've the answer for you, but I suspect that the big difference > is in the graphics subsystem, the windows more than likely supporting the > hardware acceleration and Linux (XFree I'm assuming) not.... I have had email responses from a few people. They tell me that IDL 5.5 on Linux does not use the system's OpenGL drivers even if they are available. This is because in RSI's judgement the hardware support on Linux is (as you note) rather flaky. This is likely to change in future versions. I suspect that on my system the graphics driver is so crippled that hardware rendering would not help IDL much. It doesn't make much difference under Windows. Windows describes the graphics controller as an "Intel 810 Graphics Controller Hub" with 4MB memory. That doesn't sound like much video RAM, does it? However I believe the Intel 810 can access system RAM. Anyway, it's quite possible that performance would improve significantly if I reduced the screen resolution. I will look into this and report back to the group. > I don't know what your reasons for moving to Linux were... I'm not sure myself! Better integration with other Unix systems mostly. I haven't really moved to Linux yet, just dipped my toe in the water and run back shivering. I haven't yet got my Linux setup to the stage where I can actually do productive work with it. --- Mark Hadfield m.hadfield@niwa.co.nz http://katipo.niwa.co.nz/~hadfield National Institute for Water and Atmospheric Research
creator: Mark Hadfield
date: 2002-01-29T01:55:49-00:00

Re: Object graphics under Linux: are they supposed to be that slow?
type: item
description: On Tue, 29 Jan 2002 14:55:49 +1300, Mark Hadfield <m.hadfield@niwa.co.nz> wrote: > "Steve Smith<steven_smith>" <nobody@nowhere.com> wrote in message > news:slrna5be3l.qih.nobody@pooh.nrel.gov... >> Hi Mark: >> I'm not sure I've the answer for you, but I suspect that the big > difference >> is in the graphics subsystem, the windows more than likely supporting the >> hardware acceleration and Linux (XFree I'm assuming) not.... > > I have had email responses from a few people. They tell me that IDL 5.5 on > Linux does not use the system's OpenGL drivers even if they are available. > This is because in RSI's judgement the hardware support on Linux is (as you > note) rather flaky. This is likely to change in future versions. > At least in previous versions of IDL (up to 5.2), I've heard that IDL uses the hw-accel if it's available, but maybe that's changed. I always found the idl demo Open GL stuff to be pretty snappy, but I've no 3-D apps. If you're using XFree, I guess you should say XFree doesn't support hw-accel graphics Open GL or DRI with the same scope as Windows, since XFree is not Linux (and you don't have to use it, there are commercial Xservers that will support most cards). > I suspect that on my system the graphics driver is so crippled that hardware > rendering would not help IDL much. It doesn't make much difference under > Windows. Windows describes the graphics controller as an "Intel 810 Graphics > Controller Hub" with 4MB memory. That doesn't sound like much video RAM, > does it? However I believe the Intel 810 can access system RAM. Anyway, it's > quite possible that performance would improve significantly if I reduced the > screen resolution. I will look into this and report back to the group. > I would be suprised if it didn't improve at lower screen resolutions. I would also look at the rest of the system and see that all your memory is being used, that you don't have a lot of crap running that doesn't need to (RedHat installs a lot of things you D…
creator: nobody@nowhere.com (S
date: 2002-01-29T16:25:52-00:00

Re: Object graphics under Linux: are they supposed to be that slow?
type: item
description: Several people have asked me for a copy of the program on which I based my assessment that IDL object graphics is considerably slower in Linux than in Windows. I haven't made it available yet, because it is entangled deeply in my IDL libraries; it doesn't make a very good benchmark anyway because it is event-driven and it's hard to include the timing functions. What I do have is an object-graphics benchmark program called TIME_TEST_GR2. This was originally written by Randall Frank and copyright is held by RSI. I am making it available by kind permission of Randall Frank and Karl Schultz: http://katipo.niwa.co.nz/~hadfield/gust/software/misc/time_t est_gr2.pro This version is functionally identical to the original but prints out a little more information about the window and device properties. Perhaps TIME_TEST_GR2 could be part of JD's revised benchmark suite? However it does have the drawback that it takes quite a while to run (~ 10 minutes) and you can't do much else on the system while it's running. I have also produced 3 files of TIME_TEST_GR2 output generated on my system: http://katipo.niwa.co.nz/~hadfield/gust/software/misc/ttgr2_ Windows.txt http://katipo.niwa.co.nz/~hadfield/gust/software/misc/ttgr2_ Windows_Renderer _1.txt http://katipo.niwa.co.nz/~hadfield/gust/software/misc/ttgr2_ Linux.txt The configurations are: * IDL 5.5 on Windows 2000 using RENDERER=0 (hardware) * IDL 5.5 on Windows 2000 using RENDERER=1 (software) * IDL 5.5 on Linux. This uses RENDERER=0 but, as is obvious from the DeviceInfo string, the rendering is carried out by the Mesa software library and does not access any hardware acceleration The geometric-mean elapsed time figure provides a rough ranking of the configurations: Windows RENDERER=0 4.58 s Windows RENDERER=1 3.11 s Linux 5.55 s The surprise here is that Windows is slower with RENDERER=0. So much for hardware acceleration! This suggests my graphics controller is no ball of fire. Linux lags behind both the Windows configuratio…
creator: Mark Hadfield
date: 2002-01-30T03:00:02-00:00

Re: Object graphics under Linux: are they supposed to be that slow?
type: item
description: Mark Hadfield (m.hadfield@niwa.co.nz) writes: > The configurations are: > > * IDL 5.5 on Windows 2000 using RENDERER=0 (hardware) > * IDL 5.5 on Windows 2000 using RENDERER=1 (software) > * IDL 5.5 on Linux. This uses RENDERER=0 but, as is obvious from > the DeviceInfo string, the rendering is carried out by the Mesa > software library and does not access any hardware acceleration > > The geometric-mean elapsed time figure provides a rough ranking of the > configurations: > > Windows RENDERER=0 4.58 s > Windows RENDERER=1 3.11 s > Linux 5.55 s Just to give you something to chew over, Mark. Here are my results with IDL 5.5 on Windows 2000, with a 32MB NVIDIA GeForce 2GTS graphics card. Screen resolution is 1280 by 1024 at 32 bits True-Color. Windows RENDERER=0 0.71 s Windows RENDERER=1 1.34 s That graphics card was a couple of hundred bucks, as I recall. :-) Cheers, David -- David W. Fanning, Ph.D. Fanning Software Consulting Phone: 970-221-0438, E-mail: david@dfanning.com Coyote's Guide to IDL Programming: http://www.dfanning.com/ Toll-Free IDL Book Orders: 1-888-461-0155
creator: David Fanning
date: 2002-01-30T04:55:23-00:00

Re: Object graphics under Linux: are they supposed to be that slow?
type: item
description: David Fanning <david@dfanning.com> wrote in message news:<MPG.16c12aa8f85252b59897e1@news.frii.com>... > Mark Hadfield (m.hadfield@niwa.co.nz) writes: > >> The configurations are: >> >> * IDL 5.5 on Windows 2000 using RENDERER=0 (hardware) >> * IDL 5.5 on Windows 2000 using RENDERER=1 (software) >> * IDL 5.5 on Linux. This uses RENDERER=0 but, as is obvious from >> the DeviceInfo string, the rendering is carried out by the Mesa >> software library and does not access any hardware acceleration >> >> The geometric-mean elapsed time figure provides a rough ranking of the >> configurations: >> >> Windows RENDERER=0 4.58 s >> Windows RENDERER=1 3.11 s >> Linux 5.55 s > > Just to give you something to chew over, Mark. Here are > my results with IDL 5.5 on Windows 2000, with a 32MB > NVIDIA GeForce 2GTS graphics card. Screen resolution > is 1280 by 1024 at 32 bits True-Color. > > Windows RENDERER=0 0.71 s > Windows RENDERER=1 1.34 s > > That graphics card was a couple of hundred bucks, as > I recall. :-) > > Cheers, > > David Here's another data point: PIII 750Mhz Windows NT 4. nVidia RIVA TNT2 AGP SSE. 32 bits/pixel I'd characterize this graphics card as a medium-low range card today. The driver uses the AGP port, which is good, and apparently leverages the Intel SSE instructions, which is also good. Windows RENDERER=0 9.41 s Windows RENDERER=1 2.72 s The hardware was MUCH slower at image operations. (GL is generally not a good image processor) In fact, I had to disable the image STRETCH test because it was taking way too long. The hardware really only beat out the software at texture-mapped polygons. I suppose that this hardware/driver package was tuned for the Quake-like games :-). (I should check for a driver update) While this is a great benchmark, it may not be representative of typical IDL application usage of graphics. For example, I might think that this test is a little heavy on images. This program was written to monitor the object graphics performance during de…
creator: karl_schultz
date: 2002-01-30T18:23:09-00:00