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Thread Pools

Thread pools on the JVM should usually be divided into the following three categories:

CPU-bound
Blocking IO
Non-blocking IO polling

Each of these categories has a different optimal configuration and usage pattern.

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

Screen Quick Reference

Basic

Description	Command
Start a new session with session name	`screen -S <session_name>`
List running sessions / screens	`screen -ls`
Attach to a running session	`screen -x`
Attach to a running session with name	`screen -r`

Inspired from: https://github.com/vigente/gerardus/wiki/Integrate-git-diffs-with-word-docx-files

Usage:

cd /path/to/your/repo/with/docx

sh -c "$(curl -fsSL https://gist.githubusercontent.com/ttimasdf/7965baab972b901c1f8349ce5fcb5e09/raw/setup-git-hook.sh)"

Done!

	@commands.guild_only()
	# Command cannot be used in private messages.

	@commands.dm_only()
	# Command can only be used in private messages.

	@commands.is_owner()
	# Command can only be used by the bot owner.

	@commands.is_nsfw()

	# get basic system informaton (including version)
	get system status

	# overview of hardware interfaces
	get system interface physical

	# details of a single network interface,
	get hardware nic <nic-name>

	# kind of hidden command to see more interface stats such as errors

	version: '3'
	services:
	traefik:
	restart: unless-stopped
	image: traefik:v2.0.2
	ports:
	- "80:80"
	- "443:443"
	labels:
	- "traefik.http.services.traefik.loadbalancer.server.port=8080"

	#!/bin/sh
	# This script based on linux-vm-tools for Ubuntu 22.02.
	# Thanks to https://github.com/Hinara/linux-vm-tools/ to script

	# This script is for Ubuntu 22.04 Jammy Jellyfish to download and install XRDP+XORGXRDP via
	# source.
	#
	# Major thanks to: http://c-nergy.be/blog/?p=11336 for the tips.
	#

	import { dirname } from 'node:path';
	import { fileURLToPath } from 'node:url';

	export const getFilename = (meta) => fileURLToPath(meta.url);
	export const getDirname = (meta) => dirname(getFilename(meta));

	const __filename = getFilename(import.meta);
	const __dirname = getDirname(import.meta);

	--------------------------------------------------------
	PC-8801MA の電源ユニットで使われている電解コンデンサ一覧
	--------------------------------------------------------

	C605 200V 560uF ルビコン MXP 高圧1次側平滑

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