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Favourite performance tuning tricks [closed]
...s give to someone asking me about optimisation.
We mainly use Sybase, but most of the advice will apply across the board.
SQL Server, for example, comes with a host of performance monitoring / tuning bits, but if you don't have anything like that (and maybe even if you do) then I would consider t...
How do I execute a command and get the output of the command within C++ using POSIX?
...
#include <cstdio>
#include <iostream>
#include <memory>
#include <stdexcept>
#include <string>
#include <array>
std::string exec(const char* cmd) {
std::array<char, 128> buffer;
std::string result;
std::uniqu...
How do I write a bash script to restart a process if it dies?
...ps! Don't ever do this.
ps is very unportable. While you find it on almost every UNIX system; its arguments vary greatly if you want non-standard output. And standard output is ONLY for human consumption, not for scripted parsing!
Parsing ps leads to a LOT of false positives. Take the ps aux |...
What is copy-on-write?
... also used in maintenance of instant snapshot on database servers like Microsoft SQL Server 2005. Instant snapshots preserve a static view of a database by storing a pre-modification copy of data when underlaying data are updated. Instant snapshots are used for testing uses or moment-dependent repor...
What is the difference between a directory and a folder?
Most people use the terms "folder" and "directory" interchangeably. From a programmer point of view, is there a difference, and if so, what is it? Does it depend on the OS, or is there a broad, general consensus? This at least suggests that there is a difference.
...
How to use NSCache
...ory pressure (i.e. it's caching too many values) it will release some of those values to make room.
If you can recreate those values at runtime (by downloading from the Internet, by doing calculations, whatever) then NSCache may suit your needs. If the data cannot be recreated (e.g. it's user input...
Suppress command line output
...lue of 1, which was just redirected to the null device.
This syntax is (loosely) borrowed from many Unix shells, but you do have to be careful because there are subtle differences between the shell syntax and CMD.EXE.
Update: I know the OP understands the special nature of the "file" named NUL I'm...
View the change history of a file using Git versioning
...e diffs for that revision, in case exists one.
– Marcos Oliveira
Feb 9 '12 at 21:44
4
--stat is a...
How to refer environment variable in POM.xml?
...independent. Because it's only valid in upper case form running on Windows OS. For example, ${env.M2_HOME} is valid, ${env.m2_home} is invalid, even if you defined a environment variable named m2_home.
– Jeff Liu
Aug 2 '14 at 10:45
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Becoming better at Vim [closed]
...ing Vim for quite a long time, but I'm at a level where I use insert mode most of the time, and I still use the arrow keys to move around(!).
...