| Summary: | Debian packages don't work on old CPUs (which don't support SSE) | ||
|---|---|---|---|
| Product: | LinuxSampler | Reporter: | Christoph Bodner <christoph.bodner> |
| Component: | gig::Engine | Assignee: | Christian Schoenebeck <cuse> |
| Status: | CLOSED FIXED | ||
| Severity: | blocker | ||
| Priority: | P2 | ||
| Version: | 0.5.1 | ||
| Hardware: | PC | ||
| OS: | Linux | ||
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Description
Christoph Bodner
2008-01-05 16:29:21 CET
I see two possibilities here: a) bug in LS (ALSA driver) b) problems with ALSA (plughw) try to use jack and see if the problem disappears. You can try to track down the problem by recompiling LS in debug mode and run it under gdb. When it crashes post the stack trace. The ALSA driver is a bit outdated as it only works in 16bit mode. (but should work on 24bit cards too, although samples are not outputted in 24bit) First off: which Debian packages do you use? The ones from our servers or from a certain distribution? This is important to know, since an "illegal instruction" in almost all cases is caused by compiling source code for an incompatible CPU. For example when it is compiled for a recent processor with SSE3 instruction set and you are using an older processor that doesn't support such new instructions. Which leads me to the next question: what is the exact processor type you are using? The CPU of this box is a very old Athlon-K7, running at 1200MHz, I use Debian Etch 4.0r2. The behaviour is the same when using Debian's precompiled kernel or my own modified pre-emptive 1000Hz "real time"-configured kernel. All LinuxSampler packages in use are those downloaded from your homepage, all lib*-packages from the distributions in context with LS have been replaced by yours. LS v0.4.0 from your site still works excellent, although the warning "...using plughw..." appears. As far as I can remember, a significant error message immediately before the crash of v0.5.1 talks something about libthread/disks or the like. VLC and Totem work great together with ALSA drivers of M-Audio 2496 (ice1712) under Debian, but there are clicking noise problems with Fedora 8 and "PulseAudio" (forget it) which I have not installed under Etch, of course. Next weekend I want to try the gdb-enabled testing with CVS v0.5.1. I just checked our Debian packages. The reason for your problem is that the new Debian binaries contain SSE instructions, which your old processor does not support. I'm just surprised that our Debian binaries contain SSE instructions, since we compiled it (according to the Debian standards) for i486 by default. Anyway, as Benno already suggested, you can solve this issue for now by recompiling LS for your machine. Have a look at the README files which contain detailed instructions how to compile Debian pacakges. Due to Debian's great packaging scripts this is usually straighforward. In your case you might need to override the CXXFLAGS for your machine though, so it won't compile the packages again with SSE instructions. I'll add a Debian HOWTO soon to the LS website, since for max. performance one should recompile libgig and LS for the specific machine anyway. Here is the promised Debian HOWTO:
http://linuxsampler.org/debian.html
Marking this one as blocker, as it should be handled for the upcoming release. This bug should finally be fixed with our latest Debian binary packages of linuxsampler 1.0.0 and Co. They are available from our downloads site as usual. I just checked all binaries of all new packages (including gigedit, qsampler, etc.) and they all have 0 SSE instructions, except the linuxsampler binary and liblinuxsampler, which both show 2 SSE instructions, but I think this is the hand written asm code for feature detection. So it should not be a problem on old machines. Closing this report now. |