Hengjie Hengjie

How to make faster scroll effects?

Avoid too many reflows (the browser to recalculate everything)
Use advanced CSS3 for graphic card rendering
Precalculate sizes and positions

Beware of reflows

The reflow appens as many times as there are frames per seconds. It recalculate all positions that change in order to diplay them. Basically, when you scroll you execute a function where you move things between two reflows. But there are functions that triggers reflows such as jQuery offset, scroll... So there are two things to take care about when you dynamically change objects in javascript to avoid too many reflows:

Overview

I'm tired of massive delay (500-1000 ms pings) while uploading large files. QoS helps some, but a significant portion remains due to bufferbloat (100-150ms). This leads to delay in VoIP calls and generally sluggish web browsing while uploading.

The new Codel algorithm in OpenWRT / Attitude Adjustment should help a lot. The results below show only ~5-6ms of added latency during uploads (i.e. 14ms vs 500+ms before!). Insane.

These instructions are for the TP-Link TL-WDR4300, because I got a good deal. If you have the money, buy a Netgear WNDR3800 and install CeroWRT, you'll probably see even better results.

Why the TP-Link TL-WDR4300

In short, its fully supported in OpenWRT Attitude Adjustment and works well for my needs:

Cheap

Launch Sublime Text 2 from the Mac OS X Terminal

Sublime Text 2 ships with a CLI called subl (why not "sublime", go figure). This utility is hidden in the following folder (assuming you installed Sublime in /Applications like normal folk. If this following line opens Sublime Text for you, then bingo, you're ready.

open /Applications/Sublime\ Text\ 2.app/Contents/SharedSupport/bin/subl

You can find more (official) details about subl here: http://www.sublimetext.com/docs/2/osx_command_line.html

	-- 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%'

	require 'spec_helper'

	$count = 0
	$count_each = 0
	$count_all = 0

	shared_examples_for "before :each" do
	it { should == 1 }
	it { should == 2 }
	end

	RAILS_ENV=production rake db:setup
	# produces the error below.....hmmm.....it's a no-worky
	psql:/yourprojectpath/yourproject/db/structure.sql:29: ERROR: could not open extension control file "/usr/share/postgresql/9.1/extension/hstore.control": No such file or directory

	# hstore postgresql extension needs to be installed, so....
	sudo apt-get install postgresql-contrib

	# now your extension should be available to enable so log in with psql
	psql -d yourproject_production -U yourdbuser -W

	# Configuration file for dnsmasq.
	#
	# Format is one option per line, legal options are the same
	# as the long options legal on the command line. See
	# "/usr/sbin/dnsmasq --help" or "man 8 dnsmasq" for details.

	# The following two options make you a better netizen, since they
	# tell dnsmasq to filter out queries which the public DNS cannot
	# answer, and which load the servers (especially the root servers)
	# unnecessarily. If you have a dial-on-demand link they also stop

	location /resize {
	alias /tmp/nginx/resize;
	set $width 150;
	set $height 100;
	set $dimens "";

	if ($uri ~* "^/resize_(\d+)x(\d+)/(.*)" ) {
	set $width $1;
	set $height $2;
	set $image_path $3;

	module MyApp
	class Application < Rails::Application
	if Rails.env == 'test'
	require 'diagnostic'
	config.middleware.use(MyApp::DiagnosticMiddleware)
	end
	end
	end