tomgrohl

{	scopeName = 'source.rs';
	comment = 'Rust Syntax: version 0.1';
	fileTypes = ( 'rs', 'jsx' );
	foldingStartMarker = '^.*\bfn\s*(\w+\s*)?\([^\)]*\)(\s*\{[^\}]*)?\s*$';
	foldingStopMarker = '^\s*\}';
	patterns = (
		{	name = 'meta.class.rs';
			comment = 'match stuff like: Sound.prototype = { … } when extending an object';
			match = '([a-zA-Z_?.$][\w?.$]*)\.(prototype)\s*(=)\s*';
			captures = {

jboner

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

hellerbarde

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

ruckus

** Find commmonly accessed tables and their use of indexes:

SELECT relname,seq_tup_read,idx_tup_fetch,cast(idx_tup_fetch AS numeric) / (idx_tup_fetch + seq_tup_read) AS idx_tup_pct FROM pg_stat_user_tables WHERE (idx_tup_fetch + seq_tup_read)>0 ORDER BY idx_tup_pct;

Returns output like:

       relname        | seq_tup_read | idx_tup_fetch |      idx_tup_pct       
----------------------+--------------+---------------+------------------------
 schema_migrations    |          817 |             0 | 0.00000000000000000000
 user_device_photos   |          349 |             0 | 0.00000000000000000000

Stanback

#
# CORS header support
#
# One way to use this is by placing it into a file called "cors_support"
# under your Nginx configuration directory and placing the following
# statement inside your **location** block(s):
#
#   include cors_support;
#
# As of Nginx 1.7.5, add_header supports an "always" parameter which

schickling

docker-machine import/export

Script to import and export docker-machine configurations to sync between hosts/collaborators

Export (on host A)

$ docker-machine ls
NAME       ACTIVE   DRIVER         STATE     URL                            SWARM   DOCKER    ERRORS
dev        -        digitalocean   Running   tcp://example.com:2376                 v1.10.1

alistairewj

Install PostgreSQL 10 on Ubuntu

This is a quick guide to install PostgreSQL 10 - tested on Ubuntu 16.04 but likely can be used for Ubuntu 14.04 and 17.04 as well, with one minor modification detailed below.

(Optional) Uninstall other versions of postgres

To make life simple, remove all other versions of Postgres. Obviously not required, but again, makes life simple. If you have data in your previous version of postgres that you'd like to retain, then this is not recommended. Instead, you'll have to use pg_upgrade or pg_upgradecluster.