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Mohammad Sadegh Khoeini mkhoeini

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@jboner
jboner / latency.txt
Last active June 18, 2025 10:55
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
@spion
spion / a-warning.md
Last active April 19, 2025 05:17
C++ versus V8 versus luajit versus C benchmark - (hash) tables

Warning

This benchmark has been misleading for a while. It was originally made to demonstrate how JIT compilers can do all sorts of crazy stuff to your code - especially LuaJIT - and was meant to be a starting point of discussion about what exactly LuaJIT does and how.

As a result, its not indicative of what its performance may be on more realistic data. Differences can be expected because

  1. the text will not consist of hard-coded constants
@jordelver
jordelver / gist:3073101
Created July 8, 2012 22:06
Set the Mac OS X SOCKS proxy on the command line

Set the Mac OS X SOCKS proxy on the command line

a.k.a. what to do when your ISP starts blocking sites :(

Set the SOCKS proxy to local SSH tunnel

networksetup -setsocksfirewallproxy "Ethernet" localhost 8080

To clear the domain and port

@schmurfy
schmurfy / gist:3199254
Created July 29, 2012 14:33
Install pandoc Mac OS X 10.8
# Install MacTex: http://mirror.ctan.org/systems/mac/mactex/mactex-basic.pkg
$ sudo chown -R `whoami` /usr/local/texlive
$ tlmgr update --self
$ tlmgr install ucs
$ tlmgr install etoolbox
# Install pandoc view homebrew
@cookrn
cookrn / links.md
Created November 5, 2012 05:04
Ryan Dahl on Software
@reagent
reagent / 001_health_check.rb
Created November 21, 2012 16:12
Middleware Response Handler
class HealthCheck
class Middleware
def initialize(application)
@application = application
end
def call(environment)
if environment['PATH_INFO'] == '/health-check'
if HealthCheck.healthy?
@pjlsergeant
pjlsergeant / bubble.pl
Created November 27, 2012 09:23
BubbleCharts of DB Tables
#!perl
# Display a bubble chart of DB tables, with rows and relationships to other tables
# Either run directly: perl bubble.pl
# Or with Plack: plackup bubble.pl
use strict; use warnings;
# cpanm Dancer Template DBIx::Class::Schema::Loader Data::Google::Visualization::DataTable
use Dancer;
@bendlas
bendlas / select.clj
Last active December 13, 2015 16:48
This is a draft of the current production state of my clojurescript enlive port. From the other end, I'm factoring enlive, so that its engine can work on any tree. That should enable a lot of shared code between a clj and a cljs version.
;; The macros
;; most macros here alias names from select.cljs
;; they will get used in regular calls
(ns lib.select
(:require
[clojure.string :as str]))
;; selector syntax
(defn intersection [preds]
@bendlas
bendlas / predicate.clj
Created February 13, 2013 07:00
This file is not part of the cljs port as of yet, but a tidbit from my enlive cleanup effort It shows how to implement CSS3 operations in terms of zippers, in that form it should be trivial to adapt to the DOM it's basically the predicates library from enlive, but lifted to a zipper level, so that it can work generically
(ns workbench.enlive.predicate
(:require
[clojure.zip :as z]
[workbench.enlive.engine
:refer [compile-step]]
[workbench.enlive.select
:refer [zip-select]]))
;; ## Builtin predicates
;;
@lpereira
lpereira / partial.c
Last active January 29, 2023 20:12
Partial functions in C This program illustrates a hack to create partial functions in C. The way it works is that it generates a template function (partial_template_function) with known pointers, that is later copied to a region of memory obtained with mmap(), patched up with the address and data to be passed to the real function, and then made …
/*
* Partial applied functions in C
* Leandro Pereira <[email protected]>
*/
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdint.h>
#include <stdbool.h>