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Comments

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Linux Needs Resource Management For Complex Workloads

davecb Re:Linux Cgroups are a good subset of this (161 comments)

The only thing mainframes have that Unix/Linux Resource Managers lack is "goal mode". I can't set a TPS target and have resources automatically allocated to stay at or above the target. I *can* create minimum guarantees for CPU, memory and I/O bandwidth on Linux, BSD and the Unixes. I just have to manage the performance myself, by changing the minimums.

about two weeks ago
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Obama Administration Says the World's Servers Are Ours

davecb Re:Maybe, maybe not. (749 comments)

The criteria is "the company that has the power to demand the data, has to do so if ordered by their country's courts". This probably dates back to the 16th century or earlier. Some time around the Hanseatic League...

A Canadian company with data in Outer Mongolia has to produce the data if it can. If the Outer Mongols prohibit the Canadian company from demanding it normally, the Canadians can't be ordered to produce it, because the data isn't in the Canadian company's control. If they allow it to be demanded normally, a Canadian court can get it. They have to do it via the Mongolian branch, they can't just issue court orders in Mongolia.

Your suspicion is correct: a Canadian company that controls data in the U.S. can indeed be ordered by a Canadian court to produce it .

--dave

about two weeks ago
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The Pentagon's $399 Billion Plane To Nowhere

davecb Re:Stop throwing good money after bad. (364 comments)

Canada's government of the day is using it as a money-sink. Our requirements are for a twin-engine, long-range, non-stealthy aircraft with a moderate ground-support capability, such as the F-18 Hornet we now use. They rejected the newer super hornet, and so I fear the entire programme exists only to soak up money they don't want to spend on the priorities of the other parties...

about three weeks ago
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Parents Mobilize Against States' Student Data Mining

davecb Re:Idiots... (139 comments)

It's obvious: children are prey and parents will be happy with other adults targeting them in new and interesting ways.

about 2 months ago
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Canada Poised To Buy 65 Lockheed Martin F-35 JSFs

davecb Re:No Bid Contracts! (417 comments)

I was thinking about replacing the leaders, actually. Their party need to choose a new PM, real soon!

--dave
[How about the Pirate party?]

about 2 months ago
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Canada Poised To Buy 65 Lockheed Martin F-35 JSFs

davecb Re:No Bid Contracts! (417 comments)

Most the members of the Conservative Party are not a majority of former Reform Party members any more....

I don't think they ever were: it's the leadership that's ex-Reform, and who has been acting in direct contradiction to what they espouse to their electors.

about 2 months ago
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Canada Poised To Buy 65 Lockheed Martin F-35 JSFs

davecb Re:No Bid Contracts! (417 comments)

I fear that corruption is starting to set in: the ex-Reform members who lead the current federal government used to hatewasting money. Now they're pissing it away it like drunken sailors.

Time for a change: either the party replaces the PM, or the voters replace the party.

about 2 months ago
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Hundreds of Cities Wired With Fiber, But Telecom Lobbying Keeps It Unusable

davecb Niggle: one polices one's monopolies and crooks (347 comments)

Actually one "polices" them rather than "regulating" them. It's called the "police power of the state", and refers to a lot more than the cops. Anything that gets you dragged in front of a magistrate or board who can punish you is policing

Regulation is a technical term for bylaw-like legislation, is misleading as heck, and historically is a term that lots of people in the 'States and Canada viscerally hate.

about 2 months ago
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US-EU Trade Agreement Gains Exaggerated, Say 41 Consumer Groups, Economist

davecb Sure, if the idea is to overturn laws (97 comments)

It's an excellent reason to lie, if the lies will help remove legal protections against the deal's sponsors. Dr Evil would strongly approve!

about 2 months ago
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Amazon Confirms Hachette Spat Is To "Get a Better Deal"

davecb Re:Isn't this classic anti-trust fodder (211 comments)

My publisher has such a site and sells DAISY, ePub, Mobi and PDF directly. They cannot sell them via Amazon, however. The Amazon site sells only a kindle-specific variant.

The fact that someone as major as O'Reilly has to deal with Amazon, at a price disadvantage and with significant limitations on what they're allowed to sell is typical of a monopoly, or an oligopoly with one leading member and the others doing price- and policy-following.

Monopolies are barely legal in Canada (where I am), but oligopolies and price-following are winked at. Very occasionally the government or courts will whack a leading oligopolist, but only if they are enraging the whole cell-phone-using population. Arguably they're a criminal conspiracy in restraint of trade, but as they only communicate their evil plans with each via press releases, the "secret" part of conspiracy is technically absent (;-))

about 2 months ago
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Amazon Escalates Its Battle Against Publishers

davecb Re:Not illegal (218 comments)

In the Excited States, they have to have something like 83% of the market

about 2 months ago
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Amazon Escalates Its Battle Against Publishers

davecb Re:Not illegal (218 comments)

The US used to have such laws, having suffered from significant monopoly problems in the past. It may be illegal in Canada, but it's arguably illegal everywhere else. If you sell houses in Chatham, you can't refuse to sell a house built by Bill Green, nor refuse to sell a house to Chan Hin Poon, even if you think Bill is an idiot and you hate anyone Chinese (;-))

Nor can you ask Bill for a kickback.

about 2 months ago
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Google Fiber: No Charge For Peering, No Fast Lanes

davecb Re:same old 1980s service on a new pole, sure (238 comments)

The approvals are for "add a new wire to all the poles in East Bumsquat county, with component sizes the same or smaller that standard F", rather than approval for houses. They're issued to companies who pull and maintain the wires and pay fees according to another preapproved schedule for large areas, typically a county or a region like "the south shore of Nova Scotia". If you want to pay a different fee, that takes a meeting. And, as I said, the original approvals took months of boring meetings, there and in Ontario.

about 2 months ago
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Google Fiber: No Charge For Peering, No Fast Lanes

davecb Re:or nine years sooner (238 comments)

Provinces vary: the first permission to hang cable TV on Ontario Hydro poles took months and months, but subsequent ones got rubber-stamped at subsequent monthly meetings. Nova Scotia, on the other hand, reputedly turns them around in a few days, unless you ask for something that requires a meeting.

about 2 months ago
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Google Fiber: No Charge For Peering, No Fast Lanes

davecb Re:Hedge (238 comments)

Someone had to bootstrap it, and Google stepped up, for their own normal benefit. In other locations, and after some years in the current ones, Google can offer to hand the physical fibre and the things it hooks to, to the local utility company. That moves the fibre itself into a being a common carrier, and probably a regulated monopoly if the local laws require.

about 2 months ago
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Cisco Complains To Obama About NSA Adding Spyware To Routers

davecb Cisco s moving to Toronto, as previously announced (297 comments)

Waterloo and Ottawa have more computer scientists. but Tranna has the manufacturing infrastructure, so Cisco's announced that they're moving significant parts of the company there. The first phase is $100 million, out of a $4-billion investment in Ontario. and roughly 1,700 jobs. See http://www.theglobeandmail.com...

Besides, many people fear CSE less than they do the NSA. After all, Canada's only been caught spying on Brazil, while the US was found spying on everyone on the planet (;-))

about 2 months ago
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Did Mozilla Have No Choice But To Add DRM To Firefox?

davecb So A/B test it and let the users decide! (406 comments)

Let the default download of a new firefox randonly select either with- or without-DRM. Cound the number of times the same user goes back and selects a non-default browser from a list that explicitly says whether they have DRM or not.

Done well, no-one will even notice.

In this experiment, I expect the null hypothesis will be "no-one cares", and will win (:-))

about 2 months ago
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Pedophile Asks To Be Deleted From Google Search After European Court Ruling

davecb Re:Ross Anderson ++ (370 comments)

For one, legal publishers.

Lexis Nexis and Westlaw are massive special-purpose search engines dealing in exactly this kind of data: court reports. Lexis Nexis is also well-known as a newspaper/magazine search engine.

Imagine a lawyer in the UK trying to refer to a classic interpretation and discovering the case was no longer reported, as from the point of view of one of the participants, it was "no longer relevant".

In non-EU countries, it if was a case about a minor, the page would have the names removed. Similarly, if a participant had received a pardon, they could apply to the court to remove their name from the published report. The original report would be available, of course, to lawyers willing to agree to confidentiality controls.

about 2 months ago
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Pedophile Asks To Be Deleted From Google Search After European Court Ruling

davecb Already happening in the UK (370 comments)

It's already having an effect: in the UK their privacy commission just got credit reporting company misbehavior dumped back on their plate: turns out they're the legal equivalent of search engines. Now add any other "information intermediary" like Lexis Nexis, which publishes law reports...

about 2 months ago
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Don't Be a Server Hugger! (Video)

davecb Leasing is always more expensive than buying (409 comments)

It's cheap in the short run, especially if you can't afford the hardware. That's why people used to lease time on IBM mainframes in computer centres. Now people lease time on x86s in computer centres, not realizing that buying enough for your base load is affordable, as well as cheaper in the long run.

The leasing (cloud) people just love people who don't know about costs.

about 2 months ago

Submissions

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Poul-Henning Kamp asks "Please Put OpenSSL Out of Its Misery"

davecb davecb writes  |  about 3 months ago

davecb (6526) writes "At ACM Queue, he asks we not buy into the 299-odd remaining bugs after taking out Heartbleed Instead 'we need a well-designed API, as simple as possible to make it hard for people to use it incorrectly. And we need multiple independent quality implementations of that API, so that if one turns out to be crap, people can switch to a better one in a matter of hours.'"
Link to Original Source
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Civil Liberties Association files class action for all Canadians, against spies

davecb davecb writes  |  about 4 months ago

davecb (6526) writes "The British Columbia CLA filed a class action on behalf of all Canadians, against our security services' collecting of metadata, because it allows for a profile to be created of the individuals involved. It's a tough class for a court to certify, but to qualify, the BCCLA needed a class that they knew contained people who were spied upon."
Link to Original Source
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Android is almost impenetrable to malware: Google

davecb davecb writes  |  about 5 months ago

davecb (6526) writes "Google’s Android Security chief Adrian Ludwig reported data showing that less than an estimated 0.001% of app installations on Android are able to evade the system’s multi-layered defenses and cause harm to users, seemingly contradicting F-Secure's Android Accounted For 97% of All Mobile Malware In 2013. As you might expect, they're not talking about the same thing."
Link to Original Source
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The UK's porn filter is blocking the latest League of Legends update

davecb davecb writes  |  about 6 months ago

davecb (6526) writes "Courtesy of Gamasutra, we see the UK's so-called "porn" filter is blocking game updates. As well, of course, as filtering such unimportant things as political and sexual-health sites"
Link to Original Source
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Canada (quietly) offering sanctuary to data from the U.S.

davecb davecb writes  |  about 7 months ago

davecb (6526) writes "The Toronto Star's lead article today is Canada courting U.S. web giants in wake of NSA spy scandal, an effort to convince them their customer data is safer here. This follows related moves like cisco moving R&D to Toronto. Industry Canada will neither confirm nor deny that European and U.S. companies are negotiating to move confidential data away from the U.S. This critically depends on recent blocking legislation to get around cases like U.S. v. Bank of Nova Scotia, where U.S. courts "extradited" Canadian bank records to the U.S. Contrary to Canadian law, you understand ..."
Link to Original Source
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Canada courts, patent office warns against trying to patent mathematics

davecb davecb writes  |  about a year ago

davecb (6526) writes "The Canadian Intellectial Property Office (CIPO) warns patent examiners that ..."for example, what appears on its face to be a claim for an “art” or a “process” may, on a proper construction, be a claim for a mathematical formula and therefore not patentable subject matter.” (Courtesy of Paula Bremner at Slaw)"
Link to Original Source
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Copyright trolls sue bloggers, defence lawyers

davecb davecb writes  |  about a year ago

davecb writes "Prenda Law has commenced three defamation, libel and conspiracy suits against the same people: defence lawyers, defendants and all the blogger and commentators at "Die Troll Die" and "Fight Copyright Trolls". The suits, in different state courts, each attempt to identify anyone who has criticized Prenda, fine them $200,000 each for stating their opinions, and prohibit them from ever criticizing Prenda again."
Link to Original Source
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Swedish Pirate Party Presses Charges Against Banks For WikiLeaks Blockade

davecb davecb writes  |  about a year and a half ago

davecb writes "Rick Falkvinge reports today that the Swedish Pirate Party has laid charges against at least Visa, MasterCard, and PayPal before the Finansinspektionen , for refusing to pass on money owed to Wikileaks. The overseer of bank licenses notes (in translation) that "The law states, that if there aren’t legal grounds to deny a payment service, then it must be processed.”"
Link to Original Source
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World Conference on International Telecommunications every bi tas bad as feared

davecb davecb writes  |  about a year and a half ago

davecb writes "Internet Society President, Lynn St. Amour, writes

At the conclusion of today's plenary, the Internet Society is concerned about the direction that the ITRs are taking with regards to the Internet. The Internet Society came to this meeting in the hopes that revisions to the treaty would focus on competition, liberalization, free flow of information, and independent regulation — things that have clearly worked in the field of telecommunications. Instead, these concepts seem to have been largely struck from the treaty text. Additionally, and contrary to assurances that this treaty is not about the Internet, the conference appears to have adopted, by majority, a resolution on the Internet. Amendments were apparently made to the text but were not published prior to agreement. This is clearly a disappointing development and we hope that tomorrow brings an opportunity for reconsideration of this approach.

[ISOC is the quasi-parental body of the IETF, the Internet Engineering Task Force]"
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Canadian Government introduces a new, different "unlawfull access" law

davecb davecb writes  |  more than 2 years ago

davecb writes "The Canadian Government may be shying away from the "lawful access" bill, but the same changes showed up in the new privacy act amendments. Someone with proper authority other than a warrant can ask and receive your confidential information from your ISP. The bill contains a lot more, and rather looks like a systematic attempt to lower privacy standards in the name of privacy, as described in the article Bill C-12: Safeguarding Canadians' Personal Information Act – Eroding Privacy in the Name of Privacy, at the Slaw legal blog."
Link to Original Source

Journals

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Why branch prediction doesn't help

davecb davecb writes  |  more than 5 years ago

In the discussion about IBM putatively buying Sun, we were having a side-discussion about prefetches and branch prediction.

I had forgotten why my branch prediction performance experiments had failed ("confirmed the null hypothesis") and had to go back to my notes.

It turns out that mature production software tends to be full of small blocks of error-handling and debug/logging code, which is not often used. A Smarter Colleague[TM] and I set out to test the newly-available branch prediction logic, expecting to see a significant improvement. I manually set the branch prediction bits in a large production application, only to find no detectable improvement.

The test application was Samba, so we changed the driver script to only read a few files from a ram disk, to eliminate disk I/O overheads. Still no detectable advantage from predicting the branches correctly!

Then we tried just a single few functions, under a test framework that did no I/O at all. Still nothing.

Eventually we tracjked it down to the debug/log/else logic: the branches areound it were always taken, but the branch-arounds were long enough that the next instructions were in a different icache line, and the cache-line had to be fetched.

It turned out that we had reproduced in code what our HPC colleagues see in data: the cache doesn't help if you're constantly leaping to a different cache line!

--dave

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Capacity planning in six paragraphs

davecb davecb writes  |  more than 5 years ago

An acquaintance asked about what to measure, and what tools to use, expecting to hear about vmstar, sar or the like.

However, the really interesting measurements are of the application's performance: response time and transactions per second.

Imagine you have a web site which responds in 1/10 second on average, is known to be running on a single cpu (queuing center, to be precise) and is averaging 6 transactions per second (TPS)

From that you know that the maximum performance will be 10 TPS, because ten 1/10ths fit into one second. You also know you're at 60% of the maximum, a nice safe number.

Now correlate this with your average CPU usage, network bandwidth and IO bandwidth, and you have a little estimator for what resources are needed to maintain good performance.

You also know that things will start getting bad at >8 TPS, so if you expect more business in future, you need to add more queuing centers (CPUs) with the appropriate amounts of network and disk I/O bandwidth.

You can also now use both the resource usage figures and tools that all the other folks have suggested, and watch out for growth in each of them. If the trend in their use looks like it will soon get above the number that corresponds to 8 TPS, above, then and only then do you need to start buying resources.

--dave c-b

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davecb davecb writes  |  more than 8 years ago This is a commonly reinvented wheel, and the version Stefan (metze) Metzmacher suggested in samba-technical is the round one (;-))

A maximally useful log message contains a number of fixed items, usually in a fixed-format header of some sort, and text for the human reader to use to understand the implications of the problem.

From memory, the fixed information includes enough to allow for mechanical sorting by nastiness and occasionally mechanical processing:

- date/time
- origin, meaning machine- or domain-name
- source, in some detail,, including the executable name and process id as a minimum, if applicable, and optionally the file, function and line, it is good to make this one token, for ease of parsing and resilience when one line has "sendmail:parse.c:parse_it:332:1948" and another has only "mconnect:1293"
- pre-classification, meaning the application type, error type and severity. DFAs can switch on this, and should.

The old ARPA format was error type source and severity as three decimal digits, which you still see when smtp says "250 ok". The 2 was permanent success, the 5 meant "the app", in this case smtp, and 0 was the severity. I prefer ascii, not numbers (;-))
- then the text for the human, saying the meaning of the error, the same way you're supposed to write the **meaning** of code in comments, not just say what the code does.

Syslog does about half of this, metze's did most of it.

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ARPA result codes

davecb davecb writes  |  about 9 years ago Alas, many folks don't know the old ARPAnet tricks and have to reinvent them. Often inelegantly.

One very handy pair was the ARPA command and return-code standard.

A command was four letters or less at the beginning of a line (record, packet), often monocase, so it could be treated as a 4-byte integer and switched on.

For example, smtp starts ups with
helo localhost
250 froggy Hello localhost [127.0.0.1], pleased to meet you

The "HELO" is the command, and the next line the response.

the first character is an ascii digit, where
1 means "informational message", and is rare
2 means permanent success
3 means partial success, as in a series of steps.
4 means temporary failure, such as "no space", and
5 means permanent failure

The second digit is 5 for "this app" and 9 for "the OS"

The third digit is the severity, so
599 I must close down, my CPU is on fire
is a very sever and permanent error (:-))

The fourth character is an ascii blank if the reply is complete on this line, a "-" if it continues to additional lines. For example, smtp has a help command:
help
214-2.0.0 This is sendmail version 8.12.8+Sun
214-2.0.0 Topics:
214-2.0.0 HELO EHLO MAIL RCPT DATA
214-2.0.0 RSET NOOP QUIT HELP VRFY
214-2.0.0 EXPN VERB ETRN DSN
214-2.0.0 For more info use "HELP ".
214-2.0.0 To report bugs in the implementation contact Sun Microsystems
214-2.0.0 Technical Support.
214-2.0.0 For local information send email to Postmaster at your site.
214 2.0.0 End of HELP info

The three digits and the "-" for continuation allows one to write as simple or as complex a DFA as you like, by doing trivial masking on fixed-length strings.

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