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Not All Cores Are Created Equal
joabj writes "Virginia Tech researchers have found that the performance of programs running on multicore processors can vary from server to server, and even from core to core. Factors such as which core handles interrupts, or which cache holds the needed data can change from run to run. Such resources tend to be allocated arbitrarily now. As a result, program execution times can vary up to 10 percent. The good news is that the VT researchers are working on a library that will recognize inefficient behavior and rearrange things in a more timely fashion." Here is the paper, Asymmetric Interactions in Symmetric Multicore Systems: Analysis, Enhancements and Evaluation (PDF).
It's those turny knobs. They lie.
You have to buy the one that goes to 11. You know how 10 makes the toast almost totally black? Well, what if you want your toast just a little bit more crispy? What if you want just that little bit more? That's what 11 is for. Those other toasters only go to 10, but this one goes to 11.
Help stamp out iliturcy.
I had a Pentium that DEFINITELY went to 11.
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
mine only went up to 10.998799799
It's OK. This is a Gentoo user. Getting make to work on multicore well has a significant impact on the usability of his computer.
How dare you be so modest!! You conceited bastard!!
The review for "Not All Cores Are Created Equal" was merely a two word review which simply read "Shit Sandwich".
Oh. So that's what's been doing it.
No folly is more costly than the folly of intolerant idealism. - Winston Churchill
Wow, a joke from 1995. It's true, Slashdot is at the forefront of cutting-edge humor.
I am sure you mean to say; Wow, a joke from 1994.995994999.
- Raynet --> .
That joke is so badly done it's not even funny.
1994.995994999
If you look carefully at this number, it's clearly one constructed by a human. The first '5' might be random, but the proceeding numbers do not have any specific reason to be weighted towards higher digits!!!
Thus, a more realistic semi-random number would be:
1994.995974983
- These characters were randomly selected.
Actually, your number looks more like random number string by a human as human try to avoid using long chains of same numbers when writing random numbers. But you are right, my number was made by randomly punching multiple number keys on my keyboard and those happened to register. I did then edit it so that the first digit after to dot was 9.
- Raynet --> .
I setup a build lab with around 10 machines. One of the machines ran 50% slower than the rest of the group. It was a huge puzzle, because each machine was a clone, identical hardware, etc. As it turned out, on of the guys in the lab setup the "slow" machine with a very CPU intensive screen saver. Whenever I went to tinker with it (to figure out why it was slower), the screen saver was not running.
So... look for the screen saver. It is not obvious.
... spherical frictionless inelastic computer at 0 Kelvin ...