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Pavel Popov velppa

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FWIW: I (@rondy) am not the creator of the content shared here, which is an excerpt from Edmond Lau's book. I simply copied and pasted it from another location and saved it as a personal note, before it gained popularity on news.ycombinator.com. Unfortunately, I cannot recall the exact origin of the original source, nor was I able to find the author's name, so I am can't provide the appropriate credits.


Effective Engineer - Notes

What's an Effective Engineer?

@jboner
jboner / latency.txt
Last active May 12, 2024 19:52
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference 0.5 ns
Branch mispredict 5 ns
L2 cache reference 7 ns 14x L1 cache
Mutex lock/unlock 25 ns
Main memory reference 100 ns 20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy 3,000 ns 3 us
Send 1K bytes over 1 Gbps network 10,000 ns 10 us
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD
@rgreenjr
rgreenjr / postgres_queries_and_commands.sql
Last active May 10, 2024 17:12
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%'
@ssrihari
ssrihari / clojure-learning-list.md
Last active May 6, 2024 16:25
An opinionated list of excellent Clojure learning materials

An opinionated list of excellent Clojure learning materials

These resources (articles, books, and videos) are useful when you're starting to learn the language, or when you're learning a specific part of the language. This an opinionated list, no doubt. I've compiled this list from writing and teaching Clojure over the last 10 years.

  • 🔴 Mandatory (for both beginners and intermediates)
  • 🟩 For beginners
  • 🟨 For intermediates

Table of contents

  1. Getting into the language
@steinwaywhw
steinwaywhw / One Liner to Download the Latest Release from Github Repo.md
Last active May 5, 2024 20:02
One Liner to Download the Latest Release from Github Repo
  • Use curl to get the JSON response for the latest release
  • Use grep to find the line containing file URL
  • Use cut and tr to extract the URL
  • Use wget to download it
curl -s https://api.github.com/repos/jgm/pandoc/releases/latest \
| grep "browser_download_url.*deb" \
| cut -d : -f 2,3 \
| tr -d \" \
@abstractart
abstractart / books.md
Last active April 13, 2024 00:01
Free Programming Ebooks - O'Reilly Media. Codeship free ebooks here - https://bit.ly/2oQ0knQ
@cdown
cdown / gist:1163649
Last active April 9, 2024 01:10
Bash urlencode and urldecode
urlencode() {
# urlencode <string>
old_lc_collate=$LC_COLLATE
LC_COLLATE=C
local length="${#1}"
for (( i = 0; i < length; i++ )); do
local c="${1:$i:1}"
case $c in
@jwreagor
jwreagor / EmacsKeyBinding.dict
Created March 20, 2014 18:41
Global Emacs Key Bindings for OS X
{
/* Keybindings for emacs emulation. Compiled by Jacob Rus.
*
* This is a pretty good set, especially considering that many emacs bindings
* such as C-o, C-a, C-e, C-k, C-y, C-v, C-f, C-b, C-p, C-n, C-t, and
* perhaps a few more, are already built into the system.
*
* BEWARE:
* This file uses the Option key as a meta key. This has the side-effect
* of overriding Mac OS keybindings for the option key, which generally