August 10, 2002

Black Socks

Aparently there's a good-sized market for black socks that you can order on-line. I learned this by reading The Great Socket Experiment thread over on K5.

Posted by jzawodn at 11:42 PM

OE-QuoteFix

Give this to every Outlook Express user you know. They need. All of them.

Posted by jzawodn at 05:28 PM

August 08, 2002

LinuxCare -- they're back!

According to an article at the Register, they're making software:

The software, called Levanta, is designed to reduce the cost of administering virtual Linux servers on IBM Corp eServer zSeries mainframe environments. Scheduled for general availability in October, the software is being demonstrated for the first time at the LinuxWorld Conference and Expo in San Francisco next week. It supports IBM's z/VM virtualization software version 4, releases 2 and 3, as well as SuSE Linux AG's Linux Enterprise Server 7 with kernel version 2.4 and Red Hat Inc's Linux 7.2. It is scheduled to cost from $150,000.

Yup, they're making mainframe software now. What an odd twist of fate.

Posted by jzawodn at 03:05 AM

Cross-browser CSS is Hard

So we're getting ready to launch some redesigned stuff on Yahoo! Finance and are taking the CSS plunge (finally). Even ignoring the ancient Netscape 4.x browsers, it's not easy. Looking at Galeon/Mozilla on Linux and Mozilla/IE/Opera on both XP and Mac OS X (oh, and OmniWeb on the Mac) highlights a lot of places where they don't agree. I wish I had the time to take screen-shots of each and post them. Hmm. Maybe tomorrow.

Yikes, I guess we ought to look at Konqueror too. What other browsers GUI are we missing? Yeah, I know about lynx, links, and w3m. Let me know if we're missing some.

How do others deal with this? Fall back to the tried and true table-based layout for some of the tricky items?

Oh, this will also be one of our most visible "live" uses of MySQL. More on that later.

If you'd like to see the layout in your favorite browser (one we haven't tested, maybe), let me know. Your help would be appreciated--especially if we can get a screen-shot out of the experience. (I'm way behind on the rest of my life this week as a result of all this stuff. Maybe I'll blog that story someday too. There are some important human lessons buried in this experience.)

Update: It's almost 3am again. I should really get to bed. *sigh* So much mail to catch up on...

Posted by jzawodn at 01:18 AM

August 07, 2002

Tivo Hacking Fun

If I ever get the spare time (after the book?), I'll hack my Tivo to do this too.

Posted by jzawodn at 07:12 PM

August 05, 2002

Debianizing RackShack

This thread on a RackShack support forum is amusing. Users are explaining how to remotely replace the OS that RackShack gives them with Debian GNU/Linux. Thanks to the Trained Monkey for the link.

Posted by jzawodn at 11:13 PM

It's not about a bazaar...

Bruce Sterling attempts to correct Eric Raymond's "cathedral and bazaar" metaphor with something more accurate.

It's this classic artisans-versus-factory model. It's not about a bazaar. Because bazaars are pre-industrial, they're swarming with crooked rug merchants, and pickpockets, and lepers straight out of the Arabian Nights. Open Source isn't about being some kind of canny rug merchant with an eye out to make some fast dough. Open Source, basically, is about hanging out with the cool guys.

I think he's right.

Posted by jzawodn at 11:10 AM

RateYourMusic.com RSS Feeds

How cool, you can get an RSS feed from RateYourMusic.com. I was on their home page page when I noticed the orange XML icon at the bottom. I clicked it and was pleasantly surprised to find an RSS 0.91 file streaming at me.

Posted by jzawodn at 10:53 AM

August 04, 2002

Slashcode, Journals, and RSS feeds

I'm confused. According to this Slashcode FAQ entry>, I should be able to pull an RSS feed for any user's journal. But I'll be damned if I can make it work. I keep getting a redirect when I try the URL the docs say to use.

Anyone know what magic incantation I'm missing? According to the docs, I ought to be able to get Matt's journal feed by using this url:

http://use.perl.org/journal.pl?op=rss&uid=Matts

But, as I said, it redirect me to this url instead:

http://use.perl.org/search.pl?op=journals

Grr.

If you do a view source on any journal entry or journal index page, there's no obvious link tag pointing to an RSS feed either.

Posted by jzawodn at 11:51 PM

Wireless Ethernet Bridge

I figured something like this existed but hadn't seen it until now. Apparently they're rather inexpensive too. So if you wanna put some old devices (like your SliMP3) on a wireless network, this is the way to go.

Posted by jzawodn at 11:43 PM

AmphetaDesk Outline Mode

While reading something somewhere (funny how you can easily get lost reading weblogs), I ran across a skin (replacement template, really) for AmphetaDesk, my preferred RSS aggregator. It fixes the one major beef I have with it: the fact that the size of the main page increases a lot as you add new feeds. The new template adds a nice outline mode.

I'm now running AmphetaDesk 0.94 from CVS with the new template and loving it. But I'm drooling to try this out.

Posted by jzawodn at 04:44 AM

PocketPC RSS Aggregation

If you've got a PocketPC, check this out.

PocketFeed is an RSS/RDF news aggregator that runs on the Pocket PC 2002 PDA's. Using OPML for it's blogroll, you can now take your news, blog entries, or any other type of syndicated data with you, sync it wirelessly or read it offline. So yes, you can sit in Starbucks with your PDA and read the latest news over 802.11b. If you have any questions, comments or suggestions, please feel free to use the PocketFeed mailing list.

Anyone got a PocketPC that I can, uh, borrow or review? :-)

Or does anyone have something similar for a Palm m105?

Posted by jzawodn at 04:08 AM

MySQL, Linux, FreeBSD, and Swap Space

I spent a fair amount of time of Friday trying figure out why our FreeBSD servers running MySQL 4.0.2 were doing so much better than our Linux servers running MySQL 4.0.2. They're all slaves of the same 3.23.51 master and get roughly equal query loads, thanks to our Alteon load-balancers (yes, the ones that occasionally stop working right).

What I noticed while watching each of them with mytop is that the Linux boxes seem to have far more slow queries than the FreeBSD boxes. Now the FreeBSD boxes in question are newer. They're Compaq DL-380s with dual 1.2 GHz CPUs, 2GB of RAM, and 6 36GB SCSI disks. The Linux boxes are a bit older and slower. But the difference was still surprising. Over the last 24 hours, the FreeBSD boxes had each logged 3 slow queries, while the Linux boxes had logged a few thousand of them. Clearly something was up.

So I got on the boxes and noticed something odd. The load average on the Linux machines was higher than I'd expect. Rather than being in the 0.5 - 2.0 range, it was hitting between 7 and 9 during busy times. Odd. I ran top for a while to see if I noticed anything odd. Sure enough, after a few minutes, I found the pattern. The kswapd process was using up a fair amount of CPU time--sometimes as much as 99% of one CPU.

It gets more interesting. Both Linux boxes have swap disabled. It's been that way ever since I got sick of dealing with the 2.4 kernel's brain-dead virtual memory system last year. Why would kswapd even be running on a system with no swap? I have no idea.

But I decided to do some research and see if anyone had seen this before. The closest I got was this message on the linux-kernel mailing list, a complain by MySQL AB's own Sascha Pachev.

He noted similarly odd behavior and asked that Rik look into it. Unfortunately, I haven't been able to find any follow-up messages.

So I went back to looking at the configuration on the machines in question. Both have 2GB of RAM, roughly half of which is for MySQL. I have the key_buffer set to 512M as well as the innodb_buffer_pool. That leaves 1GB for the OS cache, buffers, and related stuff. It should be more than enough, shouldn't it?

Just for the heck of it, I backed both values down to 384M and restarted MySQL. After an hour or so, things began to look bleak again. Lots of slow queries and the kswapd process (actually a kernel thread) was getting more CPU time than I'd like. It was at this point that I really began to marvel at the situation. The FreeBSD VM subsystem never does stupid things like this. In fact, our MySQL/FreeBSD boxes rarely swap unless I do something really stupid. How can the one in Linux be this much worse? Beats me.

Anyway, even more frustrated, I decided to re-enable swap reboot the machine. At this point, I had little to lose. Once it came back up and I got MySQL started, things looked okay. kswapd wasn't as busy, and there were fewer slow queries. In fact, after 1 day and 9 hours, the server has only logged 66 slow queries. But according to top there's about 47MB of swap in use. The resident size of mysqld is 736MB, while it's overall size is 816MB. Apparently the kernel swapped out part of the buffer pool for InnoDB or the MyISAM key buffer.

I guess that extra gig of memory isn't enough for it.

I fail to understand what it's doing. But the machine seems to perform better with swap enabled. The only theory I've developed so far goes like this: With swap disabled, the kernel (being very stupid), goes looking for pages that it can swap out. It finds them but cannot swap them to disk. Next time around, it repeats this process, never realizing how futile it is. With swap finally enabled, it can swap out some memory and get the breathing room that it thinks it needs.

If anyone has hints on how this can be tuned (like telling the kernel not to bother), I'd LOVE to hear about it.

Linux may have FreeBSD beat when it comes to threading, but it sure could learn a lot from FreeBSD when it comes to virtual memory management.

Update: Thanks to the folks at NewsForge, you can find a teaser for this blog entry here (and it's currently on the home page). They picked this one up quite fast. I'm impressed.

Update #2: Allow me to respond from some feedback that I've seen so far. First off, we've been running 2.4.18 for quite a while now. We started with 2.4.9, tried 2.4.12 and 2.4.16. There's only so much time I can spend switching kernel versions and re-testing. Now that 2.4.19 is out, we'll give it a shot.

A few folks have suggested that since FreeBSD is the best tool for the job, I should just shut up and use it. If only that was the case. I'll post another entry in a few days detailing the problems with running a high-volume MySQL server on FreeBSD. It has issues of it's own, mostly related to FreeBSD's poor threads implementation.

Thanks for all the feedback so far. Some of it looks promising. The flames, however, are simply ignored.

Posted by jzawodn at 02:42 AM

NoPopIE, the Internet Explorer pop-up killer!

Find it here and install it if you use Windows and IE. Works pretty well. Adds an entry to the "Tools" menu in IE so you can customize it. And best of all, it's free. :-)

Posted by jzawodn at 02:32 AM