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An Unbelievable Demo

brendangregg.com

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Re: An Unbelievable Demo

#171

Post by masklinn »

rubicon33 wrote: post #63
cperciva wrote: post #49

Reminds me of when Apple started providing "smaller size updates" to OS X. I was curious about the details since my doctorate had touched on the topic, so I worked my contacts (I had a few in Apple engineering from the FreeBSD / OS X relationship) and after a few months I got back as answer: "We're using a tool called bsdiff, are you familiar with it?" I was indeed, since I was the author of said tool. (Just to be cl…

I don't understand what bsdiff does, or is. I am a software developer and I frankly have no clue what I would ever use bsdiff for! I've read what it does (libraries for building and applying patches to binary files) and still don't really have a sense for what the purpose of this tool is. What are some real life use cases for it? When does a developer need such a tool?

> I don't understand what bsdiff does, or is.

It‘s a binary diff/patch utility.

> What are some real life use cases for it? When does a developer need such a tool?

Incrementally update binary files e.g. assets or runnable binaries instead if having to re-send the entire thing on every update so e.g. games, browsers, package managers, …

The standard diff/patch utilities are text-based and even when they do extend to binary data their algorithms and heuristics tend to be biased towards textual contents.

Bsdiff was built specifically with an eye towards executables.

Re: An Unbelievable Demo

#172

Post by mnw21cam »

oblio wrote: post #157
toyg wrote: post #132

Earlier quoted context omitted.

The single most significant factor for the popularity of American accents is Hollywood.

I'd include the US music industry in that. Songs are > important for learning a language, if you're constantly surrounded by songs of a certain language. Plus... American multinationals are somewhat close behind. If you want to get a good, well paying job at an American multinational, you have to speak English at least a bit, and you have to know it well if you want to move up the ladder.

People pronounce differently when singing vs speaking.

Re: An Unbelievable Demo

#173

Post by mewse »

maccard wrote: post #112
throwaway3699 wrote: post #75

Earlier quoted context omitted.

Implementing software updates where you don't want to ship entire binaries again (and only the diff) would be one. In some video games the assets are also packed into massive binaries, so you don't want to ship gigabytes of data because you replaced one icon. Sadly many games do this anyway nowadays.

One of the reasons games do this is the data is compressed, so a "patch" might be indistinguishable from a real update. Also, as a dev, you have no idea what version your users are updating _from_. You either need to generate some number of patches for every version you could be updating from, and figure out if you should just download the whole thing again in any of those cases anyway.

We usually don’t compress the data on disk; decompression would make loading and file access slower.

Instead, we just pack the uncompressed files together (frequently using normal zip in a no-compression mode) so that we can avoid needing to ask the OS to open and close files for us or examining the contents of a directory, both of which can be kind of startlingly slow (by video game standards) on some common OSes. Instead, we will generally cache the directory data from the zip file and just use that rather than go to disk.

(of course, the whole download/patch would all be compressed for network transfer, but files would then be decompressed during the installation process)

Re: An Unbelievable Demo

#174

Post by DonHopkins »

oblio wrote: post #120
naruhodo wrote: post #92

Earlier quoted context omitted.

Speak through your nose and and lean heavily on the R sound wherever you find it. Peter Sellers called Americans "The Herns" [1]: > Various American characters with the surname Hern or Hearn, often used for narration, outrageous announcements or parody sales pitches. The Goons referred to Americans as "herns", possibly because saying "hern hern hern...." sounded American to them, possibly because Sellers once said th…

As a non-native English speaker I absolutely hate English accents where consonants absolutely disappear for no good reason. Personally I'd rather have Americans "lean heavily on the R" than act like the letter doesn't exist (rhotic vs non-rhotic). I think it's another factor why American English is more popular than British English (besides the huge economic factor, the US economy being 5x the UK one), since their pr…

There's actually a phonetic term for "leaning heavily on the R":

https://en.wikipedia.org/wiki/Rhoticity_in_English

>Rhoticity in English is the pronunciation of the historical rhotic consonant /r/ in all contexts by speakers of certain varieties of English. The presence or absence of rhoticity is one of the most prominent distinctions by which varieties of English can be classified. In rhotic varieties, the historical English /r/ sound is preserved in all pronunciation contexts. In non-rhotic varieties, speakers no longer pronounce /r/ in postvocalic environments—that is, when it is immediately after a vowel and not followed by another vowel. For example, in isolation, a rhotic English speaker pronounces the words hard and butter as /ˈhɑːrd/ and /ˈbʌtər/, whereas a non-rhotic speaker "drops" or "deletes" the /r/ sound, pronouncing them as /ˈhɑːd/ and /ˈbʌtə/. When an r is at the end of a word but the next word begins with a vowel, as in the phrase "better apples", most non-rhotic speakers will pronounce the /r/ in that position (the linking R), since it is followed by a vowel in this case. (Not all non-rhotic varieties use the linking R; for example, it is absent in non-rhotic varieties of Southern American English.)

>The rhotic varieties of English include the dialects of South West England, Scotland, Ireland, and most of the United States and Canada. The non-rhotic varieties include most of the dialects of modern England, Wales, Australia, New Zealand, and South Africa. In some varieties, such as those of some parts of the southern and northeastern United States, rhoticity is a sociolinguistic variable: postvocalic r is deleted depending on an array of social factors such as the speaker's age, social class, ethnicity, or the degree of formality of the speech event.

Re: An Unbelievable Demo

#175

Post by TulliusCicero »

oblio wrote: post #157
toyg wrote: post #132

Earlier quoted context omitted.

The single most significant factor for the popularity of American accents is Hollywood.

I'd include the US music industry in that. Songs are > important for learning a language, if you're constantly surrounded by songs of a certain language. Plus... American multinationals are somewhat close behind. If you want to get a good, well paying job at an American multinational, you have to speak English at least a bit, and you have to know it well if you want to move up the ladder.

For regular songs (not rapping) it's a lot harder to distinguish Brits vs Americans, I've found, as compared to speaking.

Re: An Unbelievable Demo

#176

Post by user-the-name »

rorykoehler wrote: post #164
brendangregg wrote: post #33

Earlier quoted context omitted.

I was in shock, and a bit furious at being ripped off, but didn't feel there was a lot I could do about it. I edited this bit out (I was trimming the post): "You might wonder why I didn't talk about this first case publicly at the time. I'd already informed them of the problem privately and how to fix it, so there wasn't more to say. Also, Sun was the number one employer in town, and to be publicly critical could be…

Are there no legal recourse options for breaking the license so blatantly?

As he said, he did not want to burn his bridges.

Re: An Unbelievable Demo

#177

Post by brazzy »

oblio wrote: post #120
naruhodo wrote: post #92

Earlier quoted context omitted.

Speak through your nose and and lean heavily on the R sound wherever you find it. Peter Sellers called Americans "The Herns" [1]: > Various American characters with the surname Hern or Hearn, often used for narration, outrageous announcements or parody sales pitches. The Goons referred to Americans as "herns", possibly because saying "hern hern hern...." sounded American to them, possibly because Sellers once said th…

As a non-native English speaker I absolutely hate English accents where consonants absolutely disappear for no good reason. Personally I'd rather have Americans "lean heavily on the R" than act like the letter doesn't exist (rhotic vs non-rhotic). I think it's another factor why American English is more popular than British English (besides the huge economic factor, the US economy being 5x the UK one), since their pr…

That's funny. As a non-native (German) English speaker, British pronounciation seems far clearer to me than American - barring strong regional accents of course, maybe thatis what you had in mind.

Re: An Unbelievable Demo

#178

Post by oblio »

Intermernet wrote: post #170
oblio wrote: post #154

Earlier quoted context omitted.

> The obvious examples that come to mind would be sports. NZ excels in Sailing, Cricket and Rugby against much larger countries. Those are niche sports, very popular in that part of the world. They're not major sports, though. Cricket is sort of a major sport, but it's also very culturally concentrated. Outside of UK & some former UK colonies, almost nobody plays it/watches it. Does New Zealand have any famous footba…

Edmund Hillary?

I guess that counts :-)

Re: An Unbelievable Demo

#179

Post by maccard »

xmprt wrote: post #129
maccard wrote: post #112

Earlier quoted context omitted.

One of the reasons games do this is the data is compressed, so a "patch" might be indistinguishable from a real update. Also, as a dev, you have no idea what version your users are updating _from_. You either need to generate some number of patches for every version you could be updating from, and figure out if you should just download the whole thing again in any of those cases anyway.

If you know a user is on version 3 and need to update to version 5, then why not just send out all the patches between 3 and 5? Why do you need to generate a new patch for each pair of versions. It feels a bit egregious when I have to download a 100MB update just because a few characters were buffed or nerfed. More involved changes end up being over 1GB.

Because it's not just version 3 to version 5, it's version 3 to version 84.

Not all versions are made equal either - one might be a character buff, another might reorder assets in the "big huge binary blob file" for performance improvements. At a certain point, rather than downloading 30MB per update for 25 versions, and applying each incrementally (remember that you have to do them in order too), just download the full 1GB once and overwrite the whole whing.

Re: An Unbelievable Demo

#180

Post by oblio »

DonHopkins wrote: post #174
oblio wrote: post #120

Earlier quoted context omitted.

As a non-native English speaker I absolutely hate English accents where consonants absolutely disappear for no good reason. Personally I'd rather have Americans "lean heavily on the R" than act like the letter doesn't exist (rhotic vs non-rhotic). I think it's another factor why American English is more popular than British English (besides the huge economic factor, the US economy being 5x the UK one), since their pr…

There's actually a phonetic term for "leaning heavily on the R": https://en.wikipedia.org/wiki/Rhoticity_in_English >Rhoticity in English is the pronunciation of the historical rhotic consonant /r/ in all contexts by speakers of certain varieties of English. The presence or absence of rhoticity is one of the most prominent distinctions by which varieties of English can be classified. In rhotic varieties, the historic…

In my original comment:

> (rhotic vs non-rhotic).

:-)

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