NEW READERS: IT’S NOT ABOUT THE FILESYSTEM ANYMORE BUT IT’S STILL BROKEN: SEE UPDATES AT BOTTOM OF POST. Addressing filesystem performance only partly fixed it. Thanks!

Since always, I’ve had latency issues on my digital audio workstation, which is running Ubuntu Linux (currently 12.04 LTS) against a Gigabyte motherboard with 4G of RAM and a suitably symmetric four-core processor. CPUs run 20%-ish in use most of the time (and all the time for these purposes), and I never have to swap.

In this configuration, I should be able to get down to around 7ms of buffer time and not get XRUNs (data loss due to buffer overrun) in my audio chain. 14ms if I want to be safe.

In reality, I can’t make it reliably at 74ms, and that has hitches I just have to live with. To get no XRUNs or close to it I have to go up to like 260ms, which is insane. I even tried getting a dedicated root-device USB card – I’ve long assumed it was some sort of USB issue. But no.

With some new tools (latencytop in particular) I have found it. It’s the file system. Specifically, it’s in the ext3’s internal transaction logging. To wit:

EXT3: committing transaction     302.9ms
log_wait_commit                  120.3ms

If I turn off read-time updating, which I tried last night, I get rid of 90% of the XRUNs, because the file system does about 90% less transaction logging to update all those inodes with new times.

But any attempt to write – well, you can guess. Even the pure realtime kernel doesn’t help; I compiled and installed a custom build of one today, but apparently this is still atomic: I get exactly the same behaviour. I may be able to live with that to some degree, because it’s a start-and-stop-of-writes thing, and as long as it doesn’t trigger during writes, I can get by.

But it’s bullshit, and it pisses me off.

I’m currently in progress of updating ext3 to ext4. I’d like to think that would solve it, given ext4’s dramatically better performance, but I have no such assurances at this point. I genuinely thought the realtime kernel might do it.

DO YOU HAVE ANYTHING YOU CAN TELL ME, DEAR INTERNETS? Particularly about filesystem tuning. Because this shouldn’t be happening; it just shouldn’t. Honestly, three tenths of a second to commit a transaction? I’ve been places where that kind of number was reasonable; it was called 1983, and I don’t live there anymore.

Anybody?

THINGS IT IS NOT:

• Shared interrupt
• This particular hard drive (the previous drive did it too; this one is faster)
• ondemand CPU scheduling (i’m running in performance)
• this particular USB port or a USB hub or extension cord or any of the sort
• bluetooth or other random services (including search)
• Corrupt HD
• Old technology (it’s SATA; the drive is like six months old)
• lack of RT kernel. I built this RT kernel today.
• Going to be solved by installing a different operating system. Please don’t.

ETA: I got the ext3 filesystem upgraded to ext4, which made all those above numbers get dramatically smaller, but no further XRUN improvement. So I then disabled journaling, a configuration which outperforms raw ext2 in benchmarks I saw, and the machine is screamingly fast despite the RT kernel…

…and it hasn’t made one goddamn whit of difference in the remaining XRUNs. WTF, computer? WTF.

ETA2 (23:51 18 August): Okay, while screwing with the filesystem did solve many XRUN problems, there are still other XRUNs which are apparently unrelated, most notably, the master-record-enable XRUN. Even moving the project to a tmpfs RAM disk and running from there produced identical results, so I’m concluding this is an entirely separate problem.

I’ve already done pretty much everything there is to do the LinuxMusicians configuration consultation page and my setup actually passes their evaluation script. I should be golden, but I’m not. Help?

ETA3 (0:26 19 August): Every two minutes, right now, with the system mostly idle, I’m getting a burst of XRUNs. On an idle machine. But it is exactly every two minutes. And while Ardour remains on top of Top even when idle (at 10% of CPU and 13.5% of RAM), Xorg pops up just underneath it, and its CPU use spikes.

What does Xorg do every two minutes? Anybody? Seriously I have no idea.

ETA4 (13:19 19 August): ARDOUR 3 TRIGGERS SESSION SAVE EVERY TWO MINUTES BY DEFAULT. Disabling that STOPS the two-minute failures entirely. We’re back to file system adventures. Holy hell. THIS HAPPENS EVEN ON RAMDISK so it’s not filesystem or media specific. What the hell is going on here?

I haven’t, for a long while, given much of a rat’s ass about the Olympic Games. But now that the IOC has ordered GBLT athletes to stay silent about Russia’s anti-gay pogrom that extends even to them, and the Americans are telling their team to comply(!) with the Russian anti-LBGT laws, I now do care.

I am now actively against the entire project. Don’t move the Olympics; cancel them.

It won’t happen, of course. The very idea is ludicrous. Despite its redeeming elements, it’s always been deeply corrupt and frankly kind of horrible as soon as you scratch the surface. And god damn, if this is how they’re gonna roll? To hell with the whole project. Burn it down and start over.

The August edition of The Geekmusic Podcast is delayed (as you may’ve noticed), partly because the interview fell through, but mostly because I’ve been too distracted with awesome things like surprise new music and horrible things like the ongoing 2013 Cat Pee Festival.

all this, yes, all this, will soon be my urine-soaked empire

Honestly, I don’t know what we’re going to do at this point. I can’t have this going into heating season and carpet is not cheap. Neither is furniture. Me, I suspect he just doesn’t want to be an indoor cat anymore, but there are coyote out there. So that’s fun.

Anyway, that’s happening. I’ll do a mini-podcast this weekend so something is out there for August. I’ll play Kaiju Meat and talk about the soundtrack project, and pay one of the bits of it that’s substantially in-progress. Kind of a mid-project preview. That’ll be nice, won’t it?

Oh my, it seems that SFWA has finally rid itself of, well, they don’t say, but we all know which white supremacist it would be, don’t we? I don’t see how they could’ve done anything else, after he used SFWA official channels to promote an overtly-racist screed against another member of the organisation.

The fact – again, just plain fact – that he’s a white Christian male supremacist who explicitly states that only white Christian men are capable of civilisation and must therefore rule everyone else? That’s just icing on this cake.

Oh, look, Scalzi seems to be in a musical mood all of a sudden. Huh, funny. I also a song coming to mind for some reason; there’s no studio version yet, but The Mighty IF posted some audience video from a Toronto house concert, that’s a start…

In pushback and misandry, I promised to post something important and useful to guys fighting misogyny. This is your turn.

Men who try to push women out of fandoms, and out of computers, out of sciences, out of wherever; when they get misogynistic in front of you – what do they want to see happen?

Well, they want the woman to be angry, or upset, or embarrassed. That’s the goal. They want to express dominance or power, and the woman to go away. They get off on that.

But that’s only half of it.

They’re looking for your endorsement – the male endorsement – just as much. They’re excluding the designated “other,” and a big reason they’re trying to do that is to improve their group bond with you. They want confirmation and endorsement.

And it can be really hard to step up and say, “Hey, don’t be a misogynist asshole.” I get that. Most geek guys are pretty introverted and it’s hard to be the one “starting something.” As a result, much of this goes unchallenged.

But you know what it’s not so hard to do?

Frown.

Don’t laugh, even nervously; don’t smile; don’t make a pleasant face; don’t look away; don’t ignore it.

Just frown. Deny them the endorsement they seek.

That’s all. Frown, and frown clearly, and where they can see it. Make a negative expression. Not sarcastic; not even pained; no laughing, even if you intend it as mocking: it calls for a plain, old, extremely unambiguous, frown. You don’t even have to make eye contact if you don’t want to.

Frown.

Frowning denies the group bond affirmation they’re seeking. The reward is reduced – or, hopefully, outright missing. It may even make them feel bad, thanks to mirror neurons.

And the best part? They can’t even complain about it, because if they do…

…then they’re the ones “starting something.” And that gives you the advantage in whatever happens next.

It’s a small thing, but it’s a meaningful thing. I didn’t invent this; I got it from Stetson Kennedy. But I can’t use it, at least, not here; it’s the kind of thing that only people seen as in-group can do, because upset from the people they’re assaulting are the point. They want that.

But, just as much, they want that confirmation – even the neutrality which counts as acceptance – from you, and anyone else they see as a peer. They want bond confirmation from “people,” who matter, as opposed to “others,” whose anger or hurt they seek.

At very least, deny them that confirmation.

Frown.
 
 
This post is part of a series on sexism in racism in geek culture. Master post here.

ETA: Hello, Thomas Sanders and communistbakery.com followers! Nice to meet you!