Writing « Joe Auricchio

Archive for the ‘Writing’ Category

Why You Don’t Want ZFS on Mac OS X

Wednesday, March 16th, 2011

Scott told me yesterday about a company bringing Sun’s ZFS filesystem to Mac OS X, picking up where Apple left off.

To be honest, I don’t understand why someone would try porting ZFS now. What Apple offered wasn’t just a new filesystem. Users don’t care about filesystems: they are a technical detail. Instead, Apple would change Mac OS X, across the whole system, to take the best advantage of the new capabilities and guarantees ZFS offers.

“Time Machine 2″ with ZFS’s cheap easy snapshots. A new default policy to set copies=2 on important folders like ~/Documents and ~/Library/Mail – better protection for users’ data, with zero effort. Every FireWire or USB hard disk would become as smart as a Drobo. And so on. Apple would do what they always do with new technology: turn an uninteresting detail into a series of small and large fixes and features that directly improve the Mac OS X experience for all users.

Instead, this new port will be just another entry in a list of filesystems most people don’t use. The system at large won’t do anything differently to take advantage of ZFS. To get any real benefit, users will have to study ZFS and figure out how to apply it to their system. That limits it to users technically competent enough to just use Solaris or Linux.

The worst news is that this port will become a support nightmare. 10.7 will come out soon. Apple puts zero effort into maintaining compatibility for low-level system modifications. So, 10.7 will probably break ZFS. The developers will scramble to fix it. Some users will lose data in the confusion. Two years later, 10.8 will come out. It will probably break ZFS. And so on.

For those who choose ZFS on Mac OS X, the question remains: What problem are you solving? What data do you have that’s so important that you want the durability guarantees and administration capabilities of ZFS, but so unimportant that you don’t mind the unreliability and future integration worries of a filesystem your OS vendor already decided they don’t want to support?

Thanks to my Dad for the Question.

Posted in Coding, Thinking, Writing | 1 Comment »

Another political post

Tuesday, November 16th, 2010

Yeah, I do this once in a while.

Here is the voicemail I just left for California Senator Barbara Boxer. I wrote every word myself.

I think the Transportation Security Administration has gone too far. In the name of protecting us from terrorists, they are violating our constitutional rights to privacy and to freedom from unreasonable searches. Air travelers today face an unacceptable choice between two invasive and humiliating forms of search: to be seen naked on full-body scanners, or to be groped in an invasive pat-down.

I’m sure you have read the open letter from UC San Francisco faculty voicing their serious concern about the health risks of the backscatter X-ray machines. Rafi Sela, former head of the Israel Airport Authority, has given interviews recently in which he describes the machines as “useless” and easy to defeat. These machines do not make us safer, and may actually be harmful, yet the TSA has pushed them into service at great expense. There is an even greater cost these machines take: the dignity and privacy of our own bodies. I hope you will agree with me that this state of affairs is completely unacceptable.

I believe much of the money spent on the TSA would be better used on intelligence, emergency response, or – here’s a crazy idea – schools and parks. The TSA is a bad security trade-off. It is time to stop and find a different course. Senator Boxer, I hope that during tomorrow’s TSA oversight hearing, you will demand the invasive and unconstitutional full-body scanners be removed, and further, that you will question the TSA’s fundamental role and effectiveness.

I’m not happy with the last paragraph. I should have done another draft.

I wanted to say something like this, but it didn’t seem to fit, and I couldn’t get the words to say what I wanted to. So, here’s the “deleted scene”:

Security is always a trade-off: it is only gained at the expense of something else. Nothing in the world can be made one hundred percent safe. But, as we try harder and harder, the costs grow more and more dear. Now, we are buying security at the cost of the dignity and privacy of our own bodies. I believe this is completely unacceptable.

Posted in Doing, Thinking, Writing | 1 Comment »

A Political Post

Wednesday, November 5th, 2008

Dear California:

I’m ashamed to tears to live in this state. Yesterday, 4.8 million of my neighbors voted against civil rights and equal protection. Proposition 8 was never about homosexuality, or religion, or the traditional marriage ceremony: it was about government adjudication of who can engage in domestic partnership, and the answer of the people is: “Not everyone”. The beliefs of a few about things that don’t affect them have now been turned into laws trampling on the rights of many. Congratulations, California, you just passed a miscegenation law.

To everyone who thinks this is a religious issue, to all Christians who voted yes on Proposition 8 because you interpret Leviticus 18:22 as declaring homosexuality a sin and calling you to take positive action to prevent same-sex couples from being happy in such sin, may I draw your attention to the New Testament: Luke 6:36-37, Colossians 3:13, 2 Corinthians 3:6, Galatians 5:14-15, and Galatians 3:19-28 for starters. You can think homosexuality is a sin, if you want to ignore the new covenant, follow all the laws of Leviticus, and declare putting meat and dairy on the same plate a sin as well, and miss the entire point of Christianity. But even if you do that, don’t you dare condemn other people for what you call a sin. Next time, try listening to what good old JC actually said before you try to do something in his name. Hint: it’s about forgiveness and love, not about legalism.

To all of you Yes on 8 campaigners who claimed this was about protecting the marriage of straight couples from some sort of degradation of society, or about what our children would be taught in schools, or that kids need both a mother and a father or they’ll grow up to be criminals and/or homosexuals, or especially anybody holding one of those signs that said “Prop 8 = less government”, come see me sometime, and I’ll send you to whatever hell you wish. You lied through your teeth to convince otherwise reasonable but tragically uninformed people that Prop 8 was something it wasn’t. I’ve been trying to keep my feelings today mostly in disappointment and not hate: but I really really really don’t like you.

My hopes and whatever feeble prayers I dare offer are with the ACLU, Lambda Legal, and the National Center of Lesbian Rights, who are currently challenging the constitutionality of Prop 8 in the California Supreme Court; and that the Court will do the right thing and protect the rights of all people.

I should be happy with the outcome of the Presidential election. The candidate I supported won, and I think the country sent a message that we’re not happy with the way things have gone. The power of the people is passing to a younger generation and we’re going to make some changes. I should be happy, but today I just can’t be. More than anything else, I’m shocked that this happened here. This is the West Coast, the land of hippies and greenies and crazies of all sorts. If this is what 47.9% of Californians believe, what does that say about the rest of the country? How can the same country elect Barack Obama and ban gay marriage? I just don’t understand.

All right. Back to infrequent natterings about technology.

P.S. Hey, Santa Clara county, where do you think you’re going? You come right back here. Santa Clara County, you screwed up big. 33.7% of you voted against BART. What the hell?! Who voted against BART? You’d better hope there are 5,000 more uncounted absentee votes for Measure B hiding somewhere. If B finally fails when every vote is in, I will find all of you and I will beat your ass back into the real world where we need BART in the South Bay so bad it hurts.

Full disclosure on my political & religious positions: I’m an atheist who sees a lot of value in the best teachings of Christianity and all religions; the teachings that nobody can always follow because it’s actually difficult to be a good person. I have strong respect for civil liberties and the rights of individuals. I’m a bit left on welfare issues. On the other hand, I don’t trust the free market as we know it today. I’d love to, but it proves itself time and again to be a terrible servant of the public good.

Posted in Thinking, Writing | 8 Comments »

Digression about Corporate Names

Sunday, October 19th, 2008

My bike was manufactured by Kawasaki Heavy Industries.

I’ve always loved that name: Heavy Industries. Mitsubishi uses it too. Calls forth images of smelters and arc-welding and great banging puncher and stamper machines on conveyor belts, the kind the heroes of a sci-fi movie have to duck through with precise timing. The modern-day blacksmith. Dimly lit cavernous factory buildings with much steam in the air. Dungeonesque. Steel and iron and axle grease. Beautiful.

There’s a new media art group from South Korea that make Flash animations of rapidly displayed words set in time with jazz music. They’re short stories or spoken-word pieces, but read instead of heard. They call themselves Young-Hae Chang Heavy Industries, turning the name on its head, because of course all they manufacture is fundamentally just bits and pixels. Not everything on their site is safe for work.

The computer security group L0pht Heavy Industries is quite well known.

On the other hand, Kawasaki Heavy Industries makes motorcycles, ATVs, and jetskis. At first those seem like only the smallest of motor vehicles. They don’t make automobiles or trucks. The impression that gives me is that Kawasaki’s Industries aren’t as Heavy as, say, Ford. So there’s a sort of irony that I project into the name.

Of course, they actually do make large things. They build aircraft, helicopters, rolling stock (including the Shinkansen), ships, construction equipment, and energy plants. Plenty of stuff worthy of the name Heavy Industries. We don’t see much of that on this side of the Pacific, so it’s a false impression to many (American?) consumers that all Kawasaki makes is small motor vehicles.

Just some rambling, taken mostly from an email to my dad. I haven’t posted anything worthwhile here on the blog for a while, and I guess this was my desire to write popping up somewhere else.

Posted in Writing | 2 Comments »

Cars (other peoples’ and mine)

Friday, June 13th, 2008

I work in downtown La Jolla, right opposite the Ferrari/Maserati dealership. AMGs, M-series, and Porsche Ses are everyday sights. Jaguars are like Toyotas. I’m tired of seeing expensive cars. But sometimes there’s something a bit more interesting than usual…

One day on the way to work I saw someone picked up in front of a particularly large house by a chauffeured Maybach. In the words of James L. (wherever you are), “Must be nice…”

A few weeks ago I saw a Ford GT in downtown La Jolla. Really, with gas prices up to $5/gallon, you’re driving one of these? You and Jeremy Clarkson both.

$BMW Z4 with German plate \"BMW Z4\"$ The US Open is in town this week, at Torrey Pines. It’s practically across the street from campus. There are a lot more interesting cars here this week—somehow the AMGs and M-series are even more abundant than usual. I found this BMW Z4 with the German plate “BMW Z4″ nestled behind CVS. An odd place to park what I assume is BMW’s touring show car. As I drove out of the parking lot, I saw a brand new SL63 AMG and a DB9 Vantage.

I don’t say any of this out of envy, merely commentary. I don’t particularly want any of these cars.¹ In fact, I still haven’t figured out what kind of car is right for me. Fast or a smooth ride? Four-door? Hatchback? FWD, RWD? Manual or auto? Low-slung or tall and roomy? I have only the vaguest of preferences.

For now I drive my dad’s trusty old Volvo S70 T5. I say “old” because the car is well on its way to 200,000 miles, but she’s only ten years old, and she looks and feels like a young girl of only 60K.² It’s zippy enough that I can have fun on late night jaunts to campus or wherever; but it’s a Volvo, so it’s comfortable enough that I don’t really mind the six-hour nonstop service from SAN to SBP for holidays and vacations. Plus it has five cylinders, which is just neat. It’s my car and I love it.

Then again, with gas going up and up, these may be the last days of the automobile. Maybe I was born in the wrong decade? Ah well. Bring on the public transit and high-speed rail.

Except maybe a Z4M. ↩
You may note I use the female pronouns here. For some reason I never think of my car as a female, even though that’s the convention for vessels. But the turn of phrase was so nice, I couldn’t pass it up. ↩

Posted in Doing, Writing | 4 Comments »

A Reply to DJ on Drivers

Tuesday, October 16th, 2007

DJ laments there are no practical guides to driver writing.

DJ, allow me, as I so often do, to vocally disagree with you :). You seem to be making two closely related claims:

There’s no information in OS textbooks on how to structure a driver to fit into any given operating system’s driver architecture
There’s no information in OS textbooks on how drivers ought to interact with their hardware to make useful stuff happen

1. General operating systems textbooks are not the place to find this information, because if they were they wouldn’t be general operating systems textbooks.

Depth and breadth are usually a trade-off in books. If a book were so thorough and detailed in its treatment of Linux drivers that you could use it as your sole reference while writing one, it could not possibly do the same justice to drivers for Solaris, Free/Net/OpenBSD, AIX, Mac OS X/IOKit, Win32, WinNT, Vista, or any other operating system, and it surely can’t cover things like process scheduling, networking, virtual memory, filesystems, or any of those other things kernels sometimes do. The reason you read an operating systems book is to get a (necessarily) broad coverage of what all operating systems do.

If you want to get specific enough to one kernel and one subsystem that you can actually use it as a reference to build a driver, you probably want to put Modern Operating Systems back on the shelf and try Linux Device Drivers, a book focused on exactly what you see as lacking in general operating systems books.

Taking a mild divergence to head off a counterargument, it’s completely acceptable for the usual OS curriculum to exclude drivers, while including many other parts of operating systems, say, basics of concurrency. The difference in curriculum reflects the likelihood the average student will encounter the material during his career. The average programmer has very high odds of using concurrent systems sometime in his career, even more so today with the advent of multicore systems. Any more than the most basic concurrent programming (paranoid locks everywhere) involves some knowledge of what the OS is doing. In contrast, the average programmer will never be anywhere near driver code. Those who do write or maintain drivers take onto themselves responsibility to further research the field, the same way we expect those working with highly parallel systems to study a bit more than locks and semaphores.

2. I’m willing to accept that there’s little information available on actually driving hardware, but that’s because the information you’re looking for is very narrowly applicable, proprietary, distributed across the whole field, in rapid flux, and/or lacks any common principles or organization. Difficult to put that into a textbook with a ten- or twenty-year lifespan.

There’s so little information generally available about how to drive hardware because it’s intensely device-dependent. Once you get to the IO port level everything ends up pretty specific to the particular chip you’re talking to. Sure, ATA’s standard, so it’s not hard to drive a hard disk. But how about the ATA controller chip? How do you ask it to send a command and get the result? Not so standard.

The impression I get from the field (see disclaimer below) is that everybody kinda builds the hw/sw interface to be as simple as possible for the firmware and hardware guys to build. This varies fairly widely with different guys and different organizational knowledge. Firmware and hardware are extremely expensive and difficult to build correctly, and anything that can be simplified should be; anything that can be offloaded to (testable, debuggable, patchable) software should be. When everyone builds their hardware the way easiest for themselves and their organization and offloads everything else to software, everybody’s hardware will look completely different and will have completely different expectations of the driver’s role. Consequently, everybody’s drivers will look completely different.

A secondary reason for lack of standardization is that until recently most first-party drivers for mass-market hardware were closed-source. When your competitors’ specs are closed to you and your own spec is closed to them, standardization is just not possible. This is changing, though, and we’ll see what happens. There have also been notable exceptions, when an entire industry segment decided to stop being dumb and standardize. EHCI stands out as a shining example. (IDE/ATA/SATA as standard disk access might qualify, though they have their origins in ancient disk protocols defined by the operating system, not the disk vendor, and any disk had to meet that protocol or you couldn’t use it. Standardization was imposed by the OS, not agreed upon by the vendors)

In such an environment, OS books can’t really get any more specific than “Here’s how you read from or write to an I/O port” for the same reason they can’t really get any more specific than “Here’s how you read or write to a network socket”. To tell you how to use, say, FTP, is to tie themselves to today’s practice and take up paper and author’s time that could be better devoted to general principles of networking. They probably ought to describe PIO and DMA, for the same reason they describe IP and TCP. But the OS books are and should be mute on how to drive the hardware. Those rules are different between every chipmaker and every chip, and change every year and every rev. They belong in datasheets and reference manuals, not general textbooks.

Conclusion

For now, every operating system has a different driver architecture, so a general operating systems textbook can’t and shouldn’t devote too much attention to any given system. Furthermore, every piece of hardware has a different host interface, so a general operating systems textbook can’t and a driver reference book sometimes shouldn’t devote too much attention to any given piece of hardware.

The way to change this is for different kernels to agree on a driver architecture, or for different hardware makers to agree on a host interface. The first is not likely to change anytime soon; Linus is not about to chuck the bottom quarter of 2.6, Apple’s kernel team hasn’t shown signs of life lately, Sun still hates everyone, and Microsoft is still dumb.

What is changing is that host interfaces are standardizing. USB was a great leap forward in this regard. Other than the UHCI/OHCI misstep, EHCI means anybody’s host adapter works the same as any others, and device classes mean anybody’s device works the same as nay others. No more does every serial and parallel widget in the store need its own driver. Disk interfaces have long been standardized (out of necessity). I thought Ethernet NICs have a broadly-supported standard, but I can’t track it down.

Disclaimer: I’m very new to hardware design, I’ve never written a driver, and I’ve only been through the first-level undergrad operating systems course. I calls ‘em as I sees ‘em, but I may not see ‘em very well from where I stand. I welcome discussion.

Posted in Coding, Writing | 1 Comment »

On the HD-DVD key flap

Sunday, May 6th, 2007

Today, Kyle said to me:

So, you know that whole hd dvd key thing? Everyone and their grandmother knows it now, or knows where to find it. But I don’t think anyone knows what the heck to do with it.

Why did the HD-DVD key become such an issue?

Content providers: Takedown letters are not the way to stop piracy. Still less are they the way to squelch people with an agenda.

Bloggers, Diggers, etc: Copying and pasting a couple dozen bytes does not equate to taking to the streets in glorious revolution. The key’s been public for months. Those who needed it to do business (software developers and pirates) had it long ago.

Forgive me if I sound reactionary. I’m on the bloggers’ side on the whole. Certainly I’m no friend to the MPAA and RIAA. I just thought we’d been through all of this back in 2002 when DVD-Jon went to trial. It’s the same DMCA, same technology (video DRM), same fair use and anticircumvention issues. Of course, none of these issues actually came up in Johansen’s trial; they were just discussed to death on the net. I’m annoyed that this all came back a few days ago, but glad everybody shut up at the end of the day.

TMBO had a photo (sorry, no link) of a guy who tattooed the key to his chest. He’s going to feel really silly next year when nobody remembers or cares anymore, and even sillier in five when the next-next-gen formats arrive with the same folks backing them.

(I hope he feels silly already because back when we had the export restrictions fifteen years ago people did the same with strong crypto algorithms.)

Posted in Thinking, Writing | 4 Comments »

Today in Watching Good Things Die news�

Friday, March 30th, 2007

Speakeasy, the last insanely great national ISP, just got bought out by Best Buy.

Speakeasy is known in the community for giving the speeds they promise, not throttling on the last mile nor unreasonably overselling their middle mile, for not blocking any inbound or outbound traffic, and encouraging users to run personal and game servers. These are things no other ISP really does. We’d be with them today, on 6×768 DSL, if we were closer to our CO. I can personally attest to their excellent customer support: the couple of problems I had were both resolved in a ten minute phone call to actual employees (not call centers). Not bad for a company of only 300 people.

And now they’ve been bought out by Best Buy for barely a year’s revenue.

At least it’s the Best Buy business division. That means we won’t have salesdrones pressing DSL on top of service agreements. And business-facing people seem to have their stuff together, on the whole. So I’m not completely without hope. I guess we’ll know in a year or so if Best Buy nukes the management.

Posted in Thinking, Writing | 1 Comment »

Beginning of the year big ups

Tuesday, January 2nd, 2007

Shoutouts to (in no particular order):

Paul, Ava, Ben, Kelsey, Rushi, Sheenika, Jonathan, Dan, Chris, Mooneer, Stephi, Hanna, Scott, Danny, David, Nik, Jess, Brad, Bethany, D.J., Sheree, Aaron, Lily, Eric G, Auston, Mark “The Knife” “The River” Gahagan, Meg, Chi, Amrit, Tam, Amado, Rego, James, Kim, Amy, Proud, Sharon, Christine, Michael, Melissa, Christie, Eric B-D, Billy, Cody, Dylan, Brandon, Iron Jeff, The Swede, Ryan, Cano, KG, Gabe, Cha-cha, Mary (my other mother), Bilow, Flo (“zis country would be so much betteir if it weir cohvered wis a meeteir of snow!”), Kris, Amanda, Lizzie, Rose, Brigette, Kerry, Marla, Kristjiana, Iain, Mike, Van, everyone else from HS, John and Elaine, Brian, Chris, Ted, Danny, everyone else from UCSD, Bill Clabby, Jeanette Ibarra, Professors Chu, Ord, Tullsen, Sato, Ito, Pineda, and Rhodes, Gabriele, Pat, Matsumiya-sensei (wherever you are), the Big Domy (you know who the Big Domy is), and of course Teresa, Rick, Amy, and Jessie. If, somehow, I forgot you, you know you’re on there too.

Further corporate propers to:

Apple Core OS team, 2 Dogs Coffee (Morro Bay), Eventful, Fern Canyon Press (and all their endeavours), Microsoft Xbox 360 team (all right, ya done good), Nintendo, Xilinx (I hate your software but I love your hardware), most of UCSD, Google, all the backbone network operators, OmniGroup, Matz, _why, and the Ruby core team, Linux kernel developers, Red Hat/Fedora, every single man woman and child who has contributed to Debian, NoMachine, irssi.org, Freenode, GNU Project, SureFire, Streamlight, Wes Hinkle’s San Diego Volvo (Service department), and of course Apple circa 1976, for the dream and the spirit.

All of these people touched me in 2006, almost universally for the better, and made my life what it was. I look forward seeing you all in 2007.

Posted in Thinking, Writing | 6 Comments »

The terminology of compatibility

Tuesday, September 12th, 2006

My previous post pointed out to me a failing of terminology to describe compatibility. To paraphrase FOLDOC:

Backward/downward compatibility means playing DVD discs in Blu-Ray players. It is a property of the new system.
Forward/upward compatibility means DVD players were originally designed to play Blu-Ray discs with some level of degradation. It is a property of the old system. (This is not true, of course. DVD players have no idea what a Blu-Ray disc is and will spit it right out. The physical layer wasn’t designed to be gracefully forward compatible.)

I’m looking for a term that means that Blu-Ray discs were designed to be played in DVD players. It’s a property of the new system; the new system was built to work with the old system, the old system never had a clue about the new system.

Posted in Thinking, Writing | 3 Comments »

Joe Auricchio