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@pastleo
pastleo / nm_l2tp_ipsec_vpn.md
Last active February 14, 2025 08:44
setup L2TP IPSEC VPN in archlinux using NetworkManager

Quick Tips for Fast Code on the JVM

I was talking to a coworker recently about general techniques that almost always form the core of any effort to write very fast, down-to-the-metal hot path code on the JVM, and they pointed out that there really isn't a particularly good place to go for this information. It occurred to me that, really, I had more or less picked up all of it by word of mouth and experience, and there just aren't any good reference sources on the topic. So… here's my word of mouth.

This is by no means a comprehensive gist. It's also important to understand that the techniques that I outline in here are not 100% absolute either. Performance on the JVM is an incredibly complicated subject, and while there are rules that almost always hold true, the "almost" remains very salient. Also, for many or even most applications, there will be other techniques that I'm not mentioning which will have a greater impact. JMH, Java Flight Recorder, and a good profiler are your very best friend! Mea

@mdo
mdo / 00-intro.md
Last active March 4, 2025 19:03
Instructions for how to affix an Ikea Gerton table top to the Ikea Bekant sit-stand desk frame.

Ikea Bekant standing desk with Gerton table top

@thoroc
thoroc / question1.md
Last active October 20, 2020 16:47
Skyscanner HackerRank questions - Oct 2015 - Backend Developer

Find the Most Popular Destination:

Your task is to find the most popular holiday destination from a list of destinations searched for by users. You are given as standard input the integer size of the list, followed by the names of the destinations themselves. The input has the following format:

  • on the first line, the count of items in the list
  • on the subsequent lines, the name of each destination searched for, one per line (each destination is a single word with no spaces, destinations can be searched for and appear more than once) The input is correct. There is at least one destination in the input. Write a program that reads the input from stdin and then outputs out the name of the most searched for destination i.e. the destination that appears most in the list. One destination is guaranteed to be the outright winner in the input.
SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS, UNIQUE_CHECKS=0;
SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0;
SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='TRADITIONAL';
CREATE SCHEMA IF NOT EXISTS `survey_001_models_from_tables` DEFAULT CHARACTER SET latin1 COLLATE latin1_swedish_ci ;
USE `survey_001_models_from_tables` ;
-- -----------------------------------------------------
-- Table `survey_001_models_from_tables`.`organizations`
-- -----------------------------------------------------