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Why does Math.round(0.49999999999999994) return 1?
...ts, you should expect the results to differ a bit on various environments (CPU, 32- or 64-bit mode).
And, when using round or inverting matrices, etc., these bits can make a huge difference.
x64 output:
10.5 rounded is 11
10.499999999999998 rounded is 10
9.5 rounded is 10
9.499999999999998 rounde...
How can I measure the speed of code written in PHP? [closed]
...e function that is slowing everything down ^^
Note that Xdebug counts the CPU time spent by PHP ; when PHP is waiting for an answer from a Database (for instance), it is not working ; only waiting. So Xdebug will think the DB request doesn't take much time !
This should be profiled on the SQL serve...
What does Redis do when it runs out of memory?
...ood enough results. 10 Approximates very closely
# true LRU but costs more CPU. 3 is faster but not very accurate.
#
# maxmemory-samples 5
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Does “display:none” prevent an image from loading?
...of your browser's developer tools.
Note that if the browser is on a small CPU computer, not having to render the image (and layout the page) will make the whole rendering operation faster but I doubt this is something that really makes sense today.
If you want to prevent the image from loading you...
How to use QueryPerformanceCounter?
... should prevent my thread from getting rescheduled to anything but the 1st CPU core. (Which is obviously only a solution for a testing environment)
– Lucas
May 22 '13 at 11:04
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What platforms have something other than 8-bit char?
....
For instance, most early-90s developers assumed that a particular no-op CPU timing delay taking a fixed number of cycles would take a fixed amount of clock time, because most consumer CPUs were roughly equivalent in power. Unfortunately, computers got faster very quickly. This spawned the rise of...
Generating random integer from a range
...ate tens of millions of random numbers in less than a second on a standard CPU with this technique.
EDIT:
Although the above is technically correct, DSimon's answer is probably more useful in practice. You shouldn't implement this stuff yourself. I have seen a lot of implementations of rejection s...
Increasing the maximum number of TCP/IP connections in Linux
...ique allows me to use large data packets, reduce fragmentation, reduces my CPU utilization both in the user land and at kernel-level.
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Java Programming - Where should SQL statements be stored? [closed]
...k-in in the java world is interesting.
I hope you haven't paid $50000 pr CPU for Oracle Enterprise, and then only used the least common denominator in order to switch to Mysql any minute. As any good DBA will tell you, there are subtle differences between the different big name databases, especial...
What integer hash function are good that accepts an integer hash key?
... input results in a different output). The algorithm is fast except if the CPU doesn't have a built-in integer multiplication unit. C code, assuming int is 32 bit (for Java, replace >> with >>> and remove unsigned):
unsigned int hash(unsigned int x) {
x = ((x >> 16) ^ x) * ...