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@jhacksworth
jhacksworth / markdown-with-xwidget-webkit.md
Created September 3, 2020 00:43
Doom Emacs: Markdown live preview with xwidget-webkit

Doom Emacs: Markdown live preview with xwidget-webkit

I saw that there's a markdown-live-preview-mode and the var markdown-live-preview-window-function which was set to the function markdown-live-preview-window-eww. That function looks like this:

(defun markdown-live-preview-window-eww (file)
  "Preview FILE with eww.
To be used with `markdown-live-preview-window-function'."
@wildrun0
wildrun0 / compile-ffmpeg.sh
Last active October 16, 2025 08:13
Compiling ffmpeg for Raspberry Pi 4 (script only works fine on RPi OS 32bit). x64 does not support mmal (see https://github.com/raspberrypi/userland/issues/688)
#!/bin/bash
# Note that there's no libdrm because this lib cause errors
sudo apt update -y && sudo apt upgrade -y
sudo apt-get -y install \
autoconf \
automake \
build-essential \
@JonCole
JonCole / DiagnoseRedisErrors-ClientSide.md
Last active January 6, 2020 17:52
Diagnosing Redis errors caused by issues on the client side
@JonCole
JonCole / ThreadPool.md
Last active May 10, 2025 15:44
Intro to CLR ThreadPool Growth

ThreadPool Growth: Some Important Details

The CLR ThreadPool has two types of threads - "Worker" and "I/O Completion Port" (aka IOCP) threads.

  • Worker threads are used when for things like processing Task.Run(…) or ThreadPool.QueueUserWorkItem(…) methods. These threads are also used by various components in the CLR when work needs to happen on a background thread.
  • IOCP threads are used when asynchronous IO happens (e.g. reading from the network).

The thread pool provides new worker threads or I/O completion threads on demand (without any throttling) until it reaches the "Minimum" setting for each type of thread. By default, the minimum number of threads is set to the number of processors on a system.

Once the number of existing (busy) threads hits the "minimum" number of threads, the ThreadPool will throttle the rate at which is injects new threads to one thread per 500 milliseconds. This means that if your system gets a burst of work needing an IOCP thread, it will proces

@JoostKiens
JoostKiens / iBeaconCalculateDistance.js
Last active October 26, 2022 17:40
iBeacon calculate distance in meters
// Based on http://stackoverflow.com/a/20434019
function calculateAccuracy(txPower, rssi) {
if (rssi === 0) {
return -1; // if we cannot determine accuracy, return -1.
}
var ratio = rssi * 1 / txPower;
if (ratio < 1.0) {
return Math.pow(ratio, 10);
@rgreenjr
rgreenjr / postgres_queries_and_commands.sql
Last active March 14, 2026 17:03
Useful PostgreSQL Queries and Commands
-- show running queries (pre 9.2)
SELECT procpid, age(clock_timestamp(), query_start), usename, current_query
FROM pg_stat_activity
WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%'
ORDER BY query_start desc;
-- show running queries (9.2)
SELECT pid, age(clock_timestamp(), query_start), usename, query
FROM pg_stat_activity
WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%'