Hacker News: fyi1183

New comment by fyi1183 in "Temporal side-channels and you: Understanding TLBleed"

fyi1183 — Tue, 03 Jul 2018 12:49:33 +0000

Maybe the answer is "wait and see the full details when they become available", but is there an example of code that is hardened against cache side channel attacks but would be vulnerable against TLB side channel attacks?

New comment by fyi1183 in "The advantages of an email-driven Git workflow"

fyi1183 — Tue, 03 Jul 2018 06:16:20 +0000

The main problem with HTML email is that it breaks interleaved responses ("bottom posting").

Bottom posting is so useful that even Outlook users reinvent it, badly of course, using different text colours etc.

It's been decades now, why have none of the advocates of HTML emails fixed this really basic problem?

New comment by fyi1183 in "The advantages of an email-driven Git workflow"

fyi1183 — Tue, 03 Jul 2018 06:13:07 +0000

Phabricator is decent in many ways, but it's terrible at handling patch series. Most people don't seem to be aware of the feature at all, and it's not integrated at all into tools like arcanist.

New comment by fyi1183 in "500px will no longer allow photographers to license their photos under CC"

fyi1183 — Mon, 02 Jul 2018 11:30:10 +0000

I'm saying that it very well could have been intentional, yes. Not in the sense of somebody at Google targeting Blender specifically (that's possible but seems very unlikely), but in the sense of somebody at Google trying to see how far they can push forced monetisation through algorithmic coercion.

I don't think we have enough information to say for certain what really happened.

New comment by fyi1183 in "500px will no longer allow photographers to license their photos under CC"

fyi1183 — Mon, 02 Jul 2018 05:59:47 +0000

> once the humans at youtube are alerted about the problem, the videos are put back up, as in the case of the blender videos. But if it was an intentional human takedown, the videos wouldn't be put back up.

It could also have been an intentional trial balloon, to test the waters to see how much they can get away with. Politicians do that kind of thing all the time.

New comment by fyi1183 in "AMD Tackles Coming “Chiplet” Revolution With New Chip Network Scheme"

fyi1183 — Sun, 24 Jun 2018 17:33:32 +0000

There's already been an example of this with the AMD + Intel combination sold by Intel in the Hades Canyon NUC. It's an Intel CPU and an AMD GPU in a single package on some sort of interposer.

The more common approach is via SOCs though.

New comment by fyi1183 in "A Problem That Only Quantum Computers Will Ever Be Able to Solve"

fyi1183 — Fri, 22 Jun 2018 08:02:28 +0000

True. This makes me wonder if there's an oracle relative to which BQP = PH?

New comment by fyi1183 in "Linux: Introduce restartable sequences system call"

fyi1183 — Thu, 21 Jun 2018 20:24:57 +0000

I suspect that something like a heap implementation could use this. For concurrency, you want different cores to use different pools to avoid atomics. In practice, this means per-thread pools are used today, but this rseq feature seems like it would allow using per-core pools instead. That would save memory and probably be even better for cache locality when a core is shared by multiple threads.

New comment by fyi1183 in "A Problem That Only Quantum Computers Will Ever Be Able to Solve"

fyi1183 — Thu, 21 Jun 2018 20:17:13 +0000

This is basically the TCS version of a clickbait headline. It's a separation of BQP and PH by an oracle. Certainly a nice result, but to put it into context, we also have a separation of P and NP by an oracle. Yet, we are very far away from actually proving that P and NP are distinct.

New comment by fyi1183 in "No Copyright Law: The Real Reason for Germany’s Industrial Expansion? (2010)"

fyi1183 — Sun, 17 Jun 2018 07:28:40 +0000

The JavaScript that arrives at the browser is usually not source code in the way that licenses tend to define the term (which is the preferred form for modifying the program). It's usually at least minified.

It's kind of an interesting situation since it looks like source code even though it really isn't.

New comment by fyi1183 in "Learn just a little Awk (2010)"

fyi1183 — Sat, 16 Jun 2018 06:47:08 +0000

That's a nice story, but True and False are keywords in python. Such assignment attempts are a syntax error.

New comment by fyi1183 in "Ask HN: What comes after BitTorrent?"

fyi1183 — Wed, 13 Jun 2018 15:19:15 +0000

There's torrent via I2P, which provides a different anonymity-vs-performance tradeoff compared to normal BitTorrent.

I would say that BitTorrent just fits is particular design constraints fairly well, so I don't see anything replacing it without changing the use case patterns.

New comment by fyi1183 in "First atomic bet on Bitcoin Cash using new opcodes"

fyi1183 — Mon, 11 Jun 2018 19:58:36 +0000

You're right of course. Just remember to use addition mod X instead of xor in that case to combine the choices.

New comment by fyi1183 in "First atomic bet on Bitcoin Cash using new opcodes"

fyi1183 — Mon, 11 Jun 2018 16:24:06 +0000

... with a bias if X is not a power of 2.

New comment by fyi1183 in "Intel demonstrates a 28-core processor running at 5GHz"

fyi1183 — Tue, 05 Jun 2018 11:07:20 +0000

Exactly. Keep in mind that AMD is currently selling 32-core chips.

They don't go up to that insane frequency, but still. There's plenty of opportunity to shop around if you want really beefy systems, which is a very refreshing state of affairs compared to just two years ago.

New comment by fyi1183 in "Intel Announces Optane DIMMs"

fyi1183 — Wed, 30 May 2018 22:59:39 +0000

I don't really know much about memory controllers, but being able to mask at the byte level seems like an important optimization. Without that, many writes will have to do a read first to them merge the read bytes with the dirty bytes.

New comment by fyi1183 in "Python’s For - Else"

fyi1183 — Mon, 28 May 2018 06:53:40 +0000

On the other hand, when you do run across this construct in the wild, it is trivial to look up what it does and learn. I imagine that's how most people learned about it, since it doesn't exist in other languages.

In a way I find your comment contradictory: on the one hand, you appreciate and embrace that the body of common knowledge can change. On the other hand, you use the current state of common knowledge as an argument against doing things that can improve the common knowledge.

New comment by fyi1183 in "Python’s For - Else"

fyi1183 — Mon, 28 May 2018 06:47:58 +0000

The if you're talking about ends in a break.

To me and many others, having an else associated to an if that ends in break/continue/return is a code smell, because it misleadingly suggests that there are two possible paths of control flow that reach the code after the if/else, when in reality you can only reach that point through the else block.

New comment by fyi1183 in "Python’s For - Else"

fyi1183 — Mon, 28 May 2018 06:24:38 +0000

Your suggested replacement duplicates the break condition, which is not ideal for maintainability.

Also, it only happens to work due to Python's variable scoping rules. I have wished for a for-else construct in C and C++ many times: having to broaden the scope of a loop iteration variable just to duplicate a loop break check really sucks.

New comment by fyi1183 in "Python’s For - Else"

fyi1183 — Mon, 28 May 2018 06:15:50 +0000

Funny, I actually like for-else because it can simplify loop exits.

First of all, the core of a linear search loop always has two exits: the break and the normal (unsuccessful) loop exit.

But in a lookup-or-insert pattern, a regular for loop has two possible states that the system can be in at the end of the loop. With a for-else loop, you can put the or-insert part into the else block, so that there is a simpler invariant: after the loop construct, the element always exists and has been found.

I was honestly surprised by all the negativity in this thread. To offer an alternative opinion, there have been plenty of times when I missed having for-else while writing C.