So THATS it!

[swestrup]

When I inherited the machine that is now being converted into my video/file server, I noticed that it had two separate ethernet cards. I asked at the time if it had been used for something fancy, but pphaneuf said no, one of the cards was broken, so he just stuck another one in there.

A quick test showed both cards working fine, so I took one out and have been using the other ever since. Well, I just worked out that it is, indeed, 'broken'. It works perfectly well, but has a top speed of 1 Mb/sec on a 100 Mb/sec line, and that's with 100% CPU utilization.  A quick Google shows that its a known problem with how this particular card reacts to the generic network driver that is the only Linux support it has.

So, I think I'm gonna swap out the card, put its replacement back in, and see what happens to performance.

Comments

[pphaneuf.livejournal.com]

Maybe that's some kind of improvement to the driver (this does sound like some kind of horrible PIO polling mode that could conceivably be a new fallback to make it work at all), but one of the two was completely dead, when I had it before. And I think it was my "nice" 3c509, which is actually a pretty sweet card when it works, doing TCP/UDP checksumming on the card (ditching invalid packets without raising an interrupt, and allowing the host to skip checksumming, saving on CPU)...

The other one was pretty horrible too, if I remember, something like one of those awful PCI NE2000 variants, right from the stone age!

[sps.livejournal.com]

Hey, Sti.

Webigail was offline for a few hours, and now it is back but "Thunderbird can't connect securely ... because the site uses a security protocol which isn't enabled." I don't think I changed anything at this end, though I could be wrong.... [reply to work if necessary!]

[swestrup]

Sorry about that. We were offline because I borked the router and it turned out that its floppy drive had died so I couldn't boot a repair disk. I had to physically dismantle the router to pull out its hard disk, stick it in another machine, repair the configuration there, and then put it all back together.

AFAICT, I put everything back exactly the way it was, so I'm not too sure what the problem might be on your end. Perhaps you were trying while stuff was still coming back up?

[swestrup]

It was the awful PCI NE2000 that was causing the trouble. I replaced it with a newer card, and I'm now getting a solid 10 MB/sec throughput. Still not as much as I was hoping for, but a major improvement. I'll try to figure out what the latest bottleneck is later.

Anyway, I had to compile a driver for the new card and while I was mucking about in menuconfig I saw that there were a bunch of legacy-card tweaks for old NE2000 cards that I hadn't enabled. Don't know if that would have helped though, as the old card had already been replaced.

[pphaneuf.livejournal.com]

10 megabytes per second? That's pretty much 100 Mbps full tilt! Or are you running on gigabit ethernet? Or did you mean 10 megabit/sec (rather than MB/sec)?

[swestrup]

You're right, of course. I was so sleepy after staying up to get things going again that I hadn't noticed I'd confuzled Mbits and MBytes.

So, I'm actually maxing out the bandwidth between the machines for short test bursts now. That's good. I can get 93 Mbits/sec sustained, which is actually higher than I thought I could reasonably achieve.

[sps.livejournal.com]

No, still no t-bird, though the webmail is back up.... Anything interesting in the logs?

[swestrup]

I'm seeing multiple attempts to set up a secure connection to the imap port, which doesn't support it, and attempts to set up a non-secure connection to the imaps port which requires TLS...

[pphaneuf.livejournal.com]

93 Mbits/sec sustained, that's pretty sweet!