mkp's blog 2008

Check it out! It's groovelicious!

Thu, 30 Oct 2008 00:00:00 EDT

Open Source Days

Wed, 15 Oct 2008 00:00:00 EDT

My slides from Open Source Days 2008 in Copenhagen are available here.

On The Road Again

Tue, 30 Sep 2008 00:00:00 EDT

I'm back home after a couple of weeks on the road. First stop was presenting at the Linux Plumbers Conference in Portland, OR. Great city, great conference. My slides are here.

After the LPC I flew to San Jose to present at the SNIA Storage Developer Conference. I believe SNIA will eventually make the slides available to the general public.

While I was away my DSL modem at the lab blew up. It's the second modem that's gone bad within a couple of months. Something really fishy must be going on with the phone wiring in that building. Most annoying.

Underrated

Wed, 10 Sep 2008 00:00:00 EDT

Down Home Style

Fri, 15 Aug 2008 00:00:00 EDT

Persistent Drive Naming

Wed, 13 Aug 2008 00:00:00 EDT

In my two test JBOD arrays I have a whole whack of different drives. udev gives us the possibility to access disks by UUID, id, path or filesystem label. Most people use the latter. However, my test drives generally don't have filesystems on them. And certainly not filesystems with a lifetime long enough to warrant labeling.

Accessing via UUID, id or path is annoying because the names are really long. So I decided to create a set of udev rules enabling me to refer to drives based upon persistent nick names.

This way I can run fdisk /dev/fred instead of fdisk /dev/disk/by-id/scsi-SHITACHI_HUS153030VLF400_J8V1WDXA_E4TFL4M1NGDE4TH. Somewhat more convenient. At least to the humans among us.

Gimme!

Travel & Mission Accomplished

Mon, 28 Jul 2008 00:00:00 EDT

Last week was crazy! First the SNIA Summer Symposium in San Jose where we had another face-2-face in the data integrity technical workgroup. Friday, I flew to Ottawa for the Linux Symposium.

Linux Data Integrity Extensions - a reprint of my paper from the Linux Symposium proceedings.
Slides from my presentation.

Also, as of yesterday my data integrity infrastructure has been merged and will be in 2.6.27-rc1.

Bad, But Good

Sat, 14 Jun 2008 00:00:00 EDT

Perl is like poutine. It's bad. But so good. And bad. But good. Mmmhm.

Christmas Came Early This Year

Sun, 08 Jun 2008 00:00:00 EDT

Another Legend Passes

Sun, 25 May 2008 00:00:00 EDT

Bye Jimmy. So long and thanks for all the music...

Pizza

Fri, 11 Apr 2008 00:00:00 EDT

My blog appears to be turning into a food showcase here in April. I am really busy at work and consequently I have nothing else to report. Codito, ergo sum...

More Baking, More Books

Sun, 06 Apr 2008 00:00:00 EDT

Sunday morning rolls.

Books:: Pacific Modern by Raul A. Barreneche; The Green House by Alanna Stang & Christopher Hawthorne

Baking

Fri, 04 Apr 2008 00:00:00 EDT

One of the only positive side effects of being allergic to most industrially prepared food is all the awesome home baked goods I get to eat. After I make them, that is...

Needed a break from coding tonight and made rugbr�d, crispy oat cookies and brunsviger cake.

No More Involuntary Anti-Aliasing

Fri, 28 Mar 2008 00:00:00 EDT

My desktop at the office is a Dell OptiPlex GX620. It originally came with analog output only, so I invested in a Dell DVI Adapter (aka an ADD2 or SDVO card).

For a long time I used the machine with my 20" LCD panel @ 1600x1200. When that conked out after years of faithful service I got a 24" display which does 1920x1200. Unfortunately, the SDVO card in my OptiPlex (a SiI 1364)) maxes out at 1600x1200 or 165MHz. So for a while I've had to settle for a craptastic analog signal that was blurry enough to send me down history lane to the long, sleepless nights in front of a Sun 3/60.

Being allergic to blurry fonts (and thus anti-aliasing) I set out googling for an HDMI SDVO card. Today I stumbled upon the following thread. I added the following modeline and my desktop is once again crystal clear. Yay!

(mkp@mojo) ~> cvt -r 1920 1200
# 1920x1200 59.95 Hz (CVT 2.30MA-R) hsync: 74.04 kHz; pclk: 154.00 MHz
Modeline "1920x1200R"  154.00  1920 1968 2000 2080  1200 1203 1209 1235 +hsync -vsync

PS. As long as we're using stone age ~100dpi displays I'm sticking with -b&h-lucidatypewriter-medium-*-*-*-12-*-*-*-*-*-iso8859-1.

Dell Doing It Right

Mon, 24 Mar 2008 00:00:00 EDT

I keep reading all these horror stories about Dell's support but have never had the need to interact with them despite owning many pieces of Dell equipment.

Last Wednesday my main test machine stopped responding. I went to the lab and found the friendly blinkenlights emitting Your-System-Is-Toast messages.

I tried to pull the fibre channel cards and disconnect the internal drives. No go. Checked all connectors and fans. Nothing. I also tried a different power circuit just in case my power relay was acting up. But the machine remained dead.

So I called Dell Support. Less than 5 minutes on hold and then a guy named Chris picked up. I gave him the service tag of the machine and provided a concise rundown of all the things I had tried. In return he didn't bother asking me if my monitor was turned on and whether the power cord was plugged in.

We spent less than a minute walking through the support wizard and he apologized for having to spend time on this, given that it was pretty obvious what the problem was.

Chris promised to send a tech to fix the machine the next day. Now, my lab is a few blocks away in an unmanned location. And it's cold a noisy to sit there the all day waiting for somebody to show up. So I asked if they could send the the new power supply and have me install it myself. No problem! Shipping to my home address saving me a roundtrip to Oracle's Montreal office wasn't a problem either. Within a few minutes he had three-wayed a courier rep into the call to confirm shipping details.

As promised, the courier showed up the next morning with a new power supply and (just in case) and replacement motherboard. Inside the motherboard kit was a everything I'd need to swap the boards, including thermal paste and syringe. However, just replacing the power supply did the trick. I let the machine run the supplied diags CD and since it completed without a burp I left the original system board in place.

Included in the shipment were two prepaid UPS waybills for returning the defect PSU and the motherboard. A note told me to call an 800-number and arrange pickup. I did so today. The courier stopped by within a few hours, and the parts are now on their way back to Dell. I left a note in the motherboard box that I hadn't touched it to save them the trouble of figuring that out.

That's the way to do it. Thanks, Dell!

Shoveling Is Futile

Sun, 09 Mar 2008 00:00:00 EDT

I think it'll be easier to get potatoes from the supermarket...

Perogies

Sun, 02 Mar 2008 00:00:00 EDT

We made perogies tonight. Not quite as good as Baba's but not bad for a first take.

Linux Storage & Filesystem Workshop

Fri, 29 Feb 2008 00:00:00 EDT

Back from the Linux Storage & Filesystem Workshop in San Jose and a quick visit to Oracle HQ.

At LSF08 I did a presentation on the data integrity project.

I have also posted a formatted version of my article from Enterprise Open Source Magazine: Proactively Preventing Data Corruption.

Another great book: Right Hand, Left Hand by Chris McManus.

We Have Link

Fri, 08 Feb 2008 00:00:00 EDT

I have a 6-bay fibre channel disk array that--unlike the rest of my SAN setup--doesn't take 15 minutes to fire up. So it's been extremely useful for quick and easy I/O testing.

This particular model has been discontinued for a while and it only supports 1 and 2 Gbps link speeds. I recently got a batch of brand new drives that support 4 Gbps operation. And unfortunately the array backplane turned out to be incapable of negotiating link speeds with them.

First I tried to download a manual. I filled out the web form and waited for the "guaranteed next business day response"... Nothing.

Then I contacted the vendor's tech support who has been fantastic at getting back to me in the past. This time: No response. Neither from the web form, nor via email. I know this is a discontinued product, but still...

I worked around the problem by powering up the array with an old 1 Gbps drive plugged in. Once things settled down I hotplugged the 4 Gbps drives which happily went to 1 Gbps link speed. I never got the same stunt working with a 2 Gbps "bootstrap" drive. So I had to live with 1 Gbps.

But the main downside to this workaround was that I had to be in the lab every time I needed the array. Thus defeating the quick and easy criteria that was my main reason for using it in the first place.

Yesterday, I stumbled upon a manual for the array. I used the amazing powers of jumper W5 to force backplane to speed 2 Gbps. And presto! It worked.

I should point out that when I initially got the 4 Gbps disks I had tried several jumper combinations in an attempt to force link speed. But between backplane and I/O daughterboard there are many combinations.

All I really needed from the vendor's tech support was two letters: "W5". Was that really too much to ask? And why on earth don't they just put their manuals up for download?

Recent Reads

Mon, 04 Feb 2008 00:00:00 EDT

Some of the books I've enjoyed recently:

Why Things Break by Mark E. Eberhart

Arthur the Dragon King by Howard Reid

Isaac Newton by James Gleick

Why Beauty Is Truth by Ian Stewart

The New Ecological Home by Daniel D. Chiras

Roamin'

Fri, 01 Feb 2008 00:00:00 EDT

This week I went to the SNIA Winter Technical Symposum in San Jose to talk about the work I've been doing on block level data integrity in Linux.

Last night I took CalTrain up to San Francisco to see an organ show at Pearl's. Hooked up with Pete Fallico and an incredibly squeaky B-3. I also met Matt, and after the show Pete gave me a ride back to my hotel in San Jose. It was like the good ol' days, except...

Back in the day I used to go between Menlo Park/Palo Alto and the Linuxcare HQ at 650 Townsend all the time. When I got off the train at 4th and King last night I thought I'd landed on a different planet. The station was the same. But there were - uhm - other buildings around it. The whole area south of the tracks has been developed.

<LouisBalfour> Crazy! </LouisBalfour>

It was also interesting going up to 3rd and Market. My old home-away-from-home, The Argent Hotel, is now a Westin.

The Times They Are A-Changin'

10 Years of Visual Stagnation

Sat, 05 Jan 2008 00:00:00 EDT

TP	360C	560	600	600X	X22	X61s
Clock (MHz)	33	100	233	650	800	1800
RAM (MB)	4	40	64	256	384	2048
Disk (MB)	170	810	4096	6144	20000	100000
Display	680x480	800x600	1024x768	1024x768	1024x768	1024x768
Year	1994	1996	1998	2000	2002	2008