> I always figured the algorithm was much simpler, it would just use the same branch as last execution — should work fairly well.
Sure, that would work significantly better than no predictor at all. But you'd agree that a better predictor would work better, right? The missing detail might be how expensive mispredicted branches are compared to other costs. If you can go from 50% accuracy to 90% accuracy, it wouldn't be surprising to more than double your performance.
> Didn’t realize it used the input value as well, which to me makes no sense — the whole point is to avoid having to inspect the value.
It doesn't, and can't for the reasons you hint at. The reason branch prediction is necessary is that the value often isn't available yet when the branch is taken. Was there something in the article that implied the opposite?
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I wonder if Daniel's tricksy approach using a random number generator to simulate a complex pattern is misleading people here.
One of the main benefits of branch prediction is predicting the end of a loop, particularly, a loop within a loop. In assembly, a loop is just a comparison at the end and a branch back to the beginning. Assume you had a loop that always executes 8 times, or some other small fixed value. Also assume there is some reason you can't unroll that loop, and that loop is inside another loop that executes millions of times. It's a real boost to performance if you can consistently predict the end of the inner loop.
If you predicted just on the last time the loop closing branch was taken, you'd always miss the ending. But if you can remember a pattern that is longer than 8, you can always get it right. This is obviously valuable. The bigger question is how much more valuable it is to predict a loop (where "loop" might actually be a complex execution pattern across multiple branches) that is thousands long rather than just 8. But quantifying how long this pattern can be on different processors is part of the groundwork for analyzing this.
> The "silver dollar" change isn't -- it's the dime. The design was in the works before the current administration, and is only intended to be for the 250th anniversary
Referring to a dime as a dollar bothered me too. Going deeper, the absence of the olive branch is actually an intentional historical reference to the Revolutionary War, where peace was tragically lost. According to the artist who made it, the open claw is to symbolize the desire to regain it:
The image takes inspiration from the Great Seal of the United States, and represents the colonists before and during the American Revolution, Custer explained. While he included the arrows from the seal, he left out the olive branch to symbolize the fact that the colonies hadn’t yet reached peace — but left the claw open to demonstrate that they were waiting for it.
Great link. Specifically, this section is indeed a clear anwer:
Custer’s design for the tails side of the coin — which features an eagle with one empty claw and one claw holding 13 arrows — won out in the selection process.
The image takes inspiration from the Great Seal of the United States, and represents the colonists before and during the American Revolution, Custer explained. While he included the arrows from the seal, he left out the olive branch to symbolize the fact that the colonies hadn’t yet reached peace — but left the claw open to demonstrate that they were waiting for it.
Yes, this is a thing that can be done. No "derivatives" are necessary. You just figure out how many dollars worth of that particular stock your portion of the fund holds, and "sell short" that same amount of that same stock. This leaves you neutral to that stock.
Note that this is probably a terrible strategy here, though. The most likely effect of adding SpaceX to the index in the manner described is that the price of SpaceX is likely to go artificially high as the index funds fight for the very few available shares.
If you are actually going to do this, you'd probably want to sell out of the ETF before it's added, wait for SpaceX to be fully added to all the index funds, and only then simultaneously buy into the ETF and short SpaceX.
> You would think even the lowest paid employees performing routine labor at the company would be pulling in multiple 6-figure salaries.
Why would you think that? Because of Musk's reputation for magnificence and generosity? Because rich gigantic companies don't care about keeping operating costs low? Or because janitors at SpaceX require special skills that can only be obtained by paying many multiples of the market rates for standard janitors?
They have CNN currently rated as "Lean Left", changed from "Left" a few years ago due to the changes you point out. You'll need to read the fine text to see their reasoning. While there were some votes that they are now biased to Right, this was a minority position.
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