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IN vs OR in the SQL WHERE Clause
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| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
--------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 8 | 1416 | 163 (2)| 00:00:02 |
|* 1 | TABLE ACCESS ...
Remote debugging with Android emulator
...? I'm sick and tired of the emulator constantly eating half of my laptop's CPU.
8 Answers
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How to see which flags -march=native will activate?
...ggest that this is suboptimal. The output of --help=target doesn't display CPU cache information, of which the methods both elias and 42n4 below have listed. Specifically, on gcc 4.9.2 on a Phenom, the output includes these: --param l1-cache-size=64 --param l1-cache-line-size=64 --param l2-cache-siz...
NumPy: function for simultaneous max() and min()
...ngle pass would be advantageous if the array exceed the size of the larger cpu caches.
– jtaylor
Mar 7 '14 at 13:58
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Is there a generator version of `string.split()` in Python?
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This is because memory is slower than cpu and in this case, the list is loaded by chunks where as all the others are loaded element by element. On the same note, many academics will tell you linked lists are faster and have less complexity while your computer wil...
Convert a String In C++ To Upper Case
...ry/cache effects: data is hot in L1 cache the whole time, and we're purely CPU-bound.
boost::to_upper_copy<char*, std::string>(): 198.0s. Yes, Boost 1.58 on Ubuntu 15.10 is really this slow. I profiled and single-stepped the asm in a debugger, and it's really, really bad: there's a dynam...
PostgreSQL - fetch the row which has the Max value for a column
...xxx_cost values), which is a weighed function estimate of required I/O and CPU resources; you can obtain this by firing up PgAdminIII and running "Query/Explain (F7)" on the query with "Query/Explain options" set to "Analyze"
Quassnoy's query has a cost estimate of 745k (!), and completes in 1.3 s...
Wrapping synchronous code into asynchronous call
...ous API for it.
I'll proceed with the assumption that your "service" is a CPU-bound operation that must execute on the same machine as the web server.
If that's the case, then the next thing to evaluate is another assumption:
I need the request to execute faster.
Are you absolutely sure that...
How does Duff's device work?
... whether the loop is finished and jumping back to the top of the loop. The CPU can run faster when it's executing straight-line code instead of jumping.
The second aspect is the switch statement. It allows the code to jump into the middle of the loop the first time through. The surprising part to m...
Why can't enum's constructor access static fields?
...e problem solved via a nested class. Pros: it's shorter and also better by CPU consumption. Cons: one more class in JVM memory.
enum Day {
private static final class Helper {
static Map<String,Day> ABBR_TO_ENUM = new HashMap<>();
}
Day(String abbr) {
this.a...