Vaibhav Bhembre neurodrone

By default Linux distros are unoptimized in terms of I/O latency. So, here are some tips to improve that.

Most apps still don't do multi-threaded I/O access, so it's a thread-per-app which makes per-app speed always bottlenecked by single-core CPU performance (that's not even accounting for stuttering on contention between multiple processes), so even with NVMe capable of 3-6 GB/s of linear read you may get only 1-2 GB/s with ideal settings and 50-150/100-400 MB/s of un/buffered random read (what apps actually use in real life) is the best you can hope for.

All writes are heavily buffered on 3 layers (OS' RAM cache, device's RAM cache, device's SLC-like on-NAND cache), so it's difficult to get real or stable numbers but writes are largelly irrelevant for system's responsiveness, so they may be sacrificed for better random reads.

The performance can be checked by:

`fio --name=read --readonly --rw={read/randread} --ioengine=libaio --iodepth={jobs_per_each_worker's_command} --bs={4k/2M} --direct={0/1} --num

My recommended settings for setting up a slack that you plan to allow public access to. Methods for adding public users include third-party utilities like slackin (https://github.com/emedvedev/slackin-extended) which enable active user badges, or simpler methods such as using the Share Invite Link from slack itself.

SUPER IMPORTANT

If you only do two things, make it these two: Make sure to disable all app integrations. There's a bunch that aren't secure for public slacks. Either deny all, or require review by an admin: https://YOURSLACK.slack.com/apps/manage/permissions Second, disable email in the profile view: https://binaryninja.slack.com/admin/settings#display_email_addresses

The reset are optional settings that may or may not be required depending on the slack:

Kubernetes v1.16 API deprecation testing

Examples of how to test the impact of the v1.16 API deprecations and ways to debug early!

If this is the first time you're hearing of these deprecations STOP and read this blog post (thanks @vllry!).

Common misunderstandings

The exact apiVersion: value that I use in my manifest is stored on disk (etcd).

Ceph StaticSites Configuration, with HAProxy & SNI

An instructional document by Robin H Johnson robin.johnson@dreamhost.com. I wrote much of the staticsites functionality of Ceph-RGW, during during late 2015 and early 2016, based on an early prototype by Yehuda Sadeh (yehudasa). It was written for usage at Dreamhost, but developed in the open for community improvement.

It is fully functional as of Jewel v10.2.3 plus PR11280 (ceph/ceph#11280). Prior to that, neither the non-CNAME nor CNAME-to-service modes will function correctly.

These configuration files represent how to quickly set up RGW+HAProxy for staticsite serving. I've tried to make them more readable, without leaving out too many details. You are strongly recommended to run a seperate RGW instance for staticsites, on a DIFFERENT outward-faciing IP than your normal instance (and in fact, certain functionality is not supported without it).

In place of using HAProxy, you could run the second rgw instance on port 80,

This document has moved!

It's now here, in The Programmer's Compendium. The content is the same as before, but being part of the compendium means that it's actively maintained.

	groups:
	- name: datetime
	rules:
	- record: daily_saving_time_belgium
	expr: \|
	(vector(0) and (month() < 3 or month() > 10))
	or
	(vector(1) and (month() > 3 and month() < 10))
	or
	(

	#!/bin/bash

	merge_num=-2
	split_num=16

	while [[ "$(ceph health)" != "HEALTH_OK" ]]; do
	sleep 10
	done

	# Some method to set your ceph.conf file to the subfolder splitting settings you want.

	#!/usr/bin/env python

	import random
	from math import sqrt, log, pow

	NPGS = 100000 # num PGs
	R = 3 # num replicas

	# OSDs: (id, weight)
	# TODO: everything below is hard coded for exactly 4 OSDs

	#!/usr/bin/env python

	import ast
	import json
	import os
	import subprocess
	import argparse
	import sys

	FNULL = open(os.devnull, 'w')


	-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
	-- --
	-- mysql --
	-- --
	-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

	--
	-- mysql <http://sqlfiddle.com/#!9/91afb5/2>
	-- note: sqlfiddle is very stupid