On 16 Feb 2004 14:54:13 -0600 Jan Depner <eviltwin69(a)cableone.net> wrote: Yeah, that's what I would have *expected* -- so I was really surprised when the latency tests didn't work out that way. Playing PCM audio while writing, then copying, a 1.5 GB file (half again as large as my RAM, so can't RAM-cache it), with my disk over 90% full, still produced what I *think* (if I'm understanding all this correctly) are pretty good numbers (100% within 1ms of the fragment latency). But I do plan on tinkering with this, especially if the performance is troublesome when I start doing real stuff. But while the disk results looked good, the graphics results weren't very . . . -c -- Chris Metzler cmetzler(a)speakeasy.snip-me.net (remove "snip-me." to email) "As a child I understood how to give; I have forgotten this grace since I have become civilized." - Chief Luther Standing Bear

:} I have one just like it... {Gigabyte no asus {8 drives}} ...You need a better soundcard. On Mon, 16 Feb 2004 20:15:31 +0100 Robert Jonsson <robert.jonsson(a)dataductus.se> wrote: -- See these tears so blue. An ageless heart that can never mend. Tears can never dry. A judgement made can never bend. ... And I've been putting out fire with gasoline... {Dave}

On Tue, 17 Feb 2004 11:25:44 +0100 Robert Jonsson <robert.jonsson(a)dataductus.se> wrote: Yeah. 4 of them are swappable {drawers}. I keep backups, libraries and so on on disks {and dvds} I do video. Video requires lots of storage. {Most of my work is widescreen... {animated... not anamorphic} It suffers when I dump it to tape. HDs are relatively cheap. Lives resample *everything* {even 41.4} to 41.4. Dvds are 48 {DVD music lets you use ungodly high sampling rates, DVDs don't cost that much more, are perfect for surround and I've seen some components lately {audiomidi.com I think} that are optimized for higher sampling rates ...there's beginning to be a real point to it.} . I don't know if you're familiar with the mess that resampling can make of your synch or not... it can make for a real mess. Besides... 24/96 just sounds so much better... and the cost of something like an audiofile or a terratec just isn't that much. -- See these tears so blue. An ageless heart that can never mend. Tears can never dry. A judgement made can never bend. ... And I've been putting out fire with gasoline... {Dave}

RTaylor wrote: unless i'm very much mistaken, lives resample everything to 48k, not 44k1. -- The handles of a craftsman's tools bespeak an absolute simplicity, the plainest forms affording the greatest range of possibilities for the user's hand. That which is overdesigned, too highly specific, anticipates outcome; the anticipation of outcome guarantees, if not failure, the absence of grace. - William Gibson, "All Tomorrow's Parties" Jörn Nettingsmeier Kurfürstenstr 49, 45138 Essen, Germany http://spunk.dnsalias.org (my server) http://www.linuxaudiodev.org (Linux Audio Developers)

On Wed, Feb 18, 2004 at 05:30:52 -0600, RTaylor wrote: Lives resample to 48k, they appear to do that even if the source is 48k (maybe the AD and DA are on seperate clocks?), but you can prevent that to allow things like AC3 to work. - Steve

Eric Dantan Rzewnicki wrote: Eric, I do this with 1394 hard drives. Supported by most laptops, low cost to add 1394 to a desktop if the MB doesn't already have it, and fast recovery when you need to get something from the backup. Think 1394 or USB. Drives are cheap these days and store far more than DVD. I do use DVDs and CDRW for backing up individual projects that I know I'm finished with and want a smaller form of media to put int he safe deposit box outside my house. (In case of fire, etc.) Cheers, Mark

On Tue, 17 Feb 2004 00:56:43 -0600 RTaylor <ricktaylor(a)speakeasy.net> wrote: I do. It's on my list of "must-do-when-have-some-$". -c -- Chris Metzler cmetzler(a)speakeasy.snip-me.net (remove "snip-me." to email) "As a child I understood how to give; I have forgotten this grace since I have become civilized." - Chief Luther Standing Bear

On Mon, 16 Feb 2004 20:15:31 +0100 Robert Jonsson <robert.jonsson(a)dataductus.se> wrote: Hi. Thanks for your reply! I have read it, if you're referring to: http://www.djcj.org/LAU/guide/Low_latency-Mini-HOWTO.php3 and I've spent a fair amount of time googling around for other low- latency suggestions/comments, such as the ones on the LAD site. My understanding is that the only higher-priority IRQs than IRQ10 are 0, 1, 8 and 9; and 0, 1 and 8 are taken. I know that IRQ10 isn't optimal for the soundcard -- that IRQ9 would be better -- but I didn't want to start screwing around with IRQ assignment until I was sure I needed to, because it's something I'm still fairly ignorant about. My BIOS does allow me to assign IRQs to PCI slots -- so I could force the soundcard onto IRQ09 -- but I don't seem to be able to monkey with the IRQs assigned to the four IDE channels, or AGP, or USB or IEEE-1394. Fortunately I'm not using any USB or Firewire devices at all, so I don't expect interrupts to be generated for them; but certainly for the disks and video card there will be. But despite the fact that two of my four IDE controllers sit on the one IRQ with higher priority than the soundcard, heavy disk use doesn't seem to cause me that much trouble. At least, it didn't in the low-latency-png test I tried (mentioned in the previous email). It was video that caused the trouble, and video sits on IRQ11, of lower priority than the soundcard on IRQ10. 09 -- IDE2, IDE3, USB1 10 -- IEEE-1394, USB2, SBLive 11 -- USB1, AGP 12 -- mouse 13 -- 14 -- IDE0 15 -- IDE1 03 -- ttyS01 04 -- ttyS00 05 -- NIC 06 -- 07 -- parallel printer It does. I will. I woulda naively figured that (among other things) faster meant "releases the kernel's attention more speedily" or something like that. But maybe not. Maybe it also means "asks for stuff more frequently" too. We'll see. I didn't think about this at all, and it's definitely a possibility now that I do think about it. I'm using XF86 4.2 rather than 4.3 because I'm a Debianista running "sarge", the release that's being assembled right now and is targeted for this summer. X 4.3 hasn't made it into Debian yet, even in its "unstable" distribution. This matters because the Matrox driver in XF86 4.2 doesn't explicitly support my video card. It *does* support the G400, the immediately previous version; but not the G550. The G550 is supported in XF86 4.3. I wouldn't have immediately thought of this because I've never run into an issue with 2D before; the driver I've used has done fine. The only problems I've had in the past has been with 3D/DRI/OpenGL stuff -- odd lockups running FlightGear, for instance. But for 2D it's been fine. But now I'm wondering. Matrox themselves provide (open-sourced!) drivers for their cards; but they're basically the same code as the XF86 versions. At one point, trying to run down the 3D issue, I switched to theirs for a while. It didn't help. Anyway, this is definitely something to think about, thanks muchly. But other than try to backport XF86 4.3, I'm not sure what I can do in response . . . I'm OK here. I'm usually under GNOME, and I've worried about that a little for when I get to doing more serious stuff. But in the meantime, the X11 stress test done in the low-latency test suite seems oblivious to desktop environment. It grabs a chunk of screen in the corner and draws on it in a way that looks very libXt and nothing else. No, these were good. Thanks. -c P.S. cc'd to make sure you'd see the response, because I couldn't respond for a day. Sorry/let me know if CCs annoy. -- Chris Metzler cmetzler(a)speakeasy.snip-me.net (remove "snip-me." to email) "As a child I understood how to give; I have forgotten this grace since I have become civilized." - Chief Luther Standing Bear

OK, I can finally come back to this now. On Tue, 17 Feb 2004 11:49:08 +0100 (MET) Clemens Ladisch <clemens(a)ladisch.de> wrote: Bingo. It helped my latency numbers *tremendously*. Every rep during the X11 stress tests came down to less than 1ms above the fragment latency -- everything. Unfortunately, it also made the desktop itself a real pain in the butt to use. I can't imagine tweaking controls in e.g. Ardour, attempting to find a set of parameters I like for something, given how sluggish the desktop was. So what are my options here? It's my understanding that the driver available from Matrox directly is the same as that for XFree86, just with some additional support for Matrox software ("PowerDesk"); so dumping XF86's driver in favor of one from the card maker isn't likely to pay off. Track down another video card? Ironic given that in that other OS, this is a highly recommended card for DAWs, and that the reason I got it was that the mfr was considered the most friendly to open source. -c P.S. CC'ing you because it took me so long to respond; hope that's OK. -- Chris Metzler cmetzler(a)speakeasy.snip-me.net (remove "snip-me." to email) "As a child I understood how to give; I have forgotten this grace since I have become civilized." - Chief Luther Standing Bear

Hi. I'm sorry for my tardiness in replying to this; it's been a really difficult last couple of weeks. I'm CC'ing you directly as well because of it being so long; hope that's OK. On Tue, 17 Feb 2004 16:01:36 +0100 Maarten de Boer &lt;mdeboer(a)iua.upf.es&gt; wrote: Yeah, when I first read your message, I went hunting in the archives and found that thread. Before my original post, I'd searched the archives on "latency" and got a zillion responses, too many to read; but it never occurred to me to search on "Matrox". Duh. Anyway, that was an interesting thread, thanks. Looking at the 2.4.23 sources, it doesn't look like that patch (from Jussi Laako) has been merged in to the kernel source; looking at the diffs in the lowlatency patch, it doesn't look like they're there, either. (although it's odd; there's a diff for mga_dma.c present in the LL patch -- that's the same file patched in Jussi Laako's patch -- but the diff is empty. It's as if Andrew Morton set up to do it, and then didn't. So I guess I'm wondering how to proceed at this point. I could ask Andrew Morton what he thought of the patch, and if there was some reason it didn't make it into his LL patch. I could troll here for people who've been using it for a while, to see what they think. I could just apply it and see what happens . . .if you have any thoughts/suggestions, I'd be grateful. Anyway, thanks muchly. -c P.S. <off-topic> I find everything with DRI and hardware acceleration in Linux almost impossible to understand. Maybe I'd get it if I were a kernel or X hacker; but as it stands, from the outside, it's impenetrable. Case in point: the lockups I mentioned in another post when doing very intensive 3D/OpenGL stuff. At one point, I did a lot of research, and came up with the following possibilities: 1. A problem with the kernel's support for my motherboard's chipset -- various people had complained about such lockups (during 3D endering) for Via chipsets on the LKML. 2. A problem with the kernel modules for my video card. 3. A problem with the XFree86 modules for my video card. 4. A problem with the Mesa (OpenGL) libraries. Without understanding these components in a fair amount of detail, it's impossible to figure out where the problem is coming from, and thus impossible to file a useful bug report (against what do I file it?). So here I am a year and a half later, still not able to do OpenGL, except for the simplest things like glxgears and occasionally tuxracer (but sometimes even that causes a lockup). Anyway. </off-topic> -- Chris Metzler cmetzler(a)speakeasy.snip-me.net (remove "snip-me." to email) "As a child I understood how to give; I have forgotten this grace since I have become civilized." - Chief Luther Standing Bear