小知了 xiaozhiliaoo

General links:

Slides for this session (from Percona Live Santa Clara 2017)
DBAs, A Priesthood No More - Silvia Botros
Ozar's Hierarchy of Database Needs - Brent Ozar

Config management:

Scaling your API with rate limiters

The following are examples of the four types rate limiters discussed in the accompanying blog post. In the examples below I've used pseudocode-like Ruby, so if you're unfamiliar with Ruby you should be able to easily translate this approach to other languages. Complete examples in Ruby are also provided later in this gist.

In most cases you'll want all these examples to be classes, but I've used simple functions here to keep the code samples brief.

Request rate limiter

This uses a basic token bucket algorithm and relies on the fact that Redis scripts execute atomically. No other operations can run between fetching the count and writing the new count.

Code is clean if it can be understood easily – by everyone on the team. Clean code can be read and enhanced by a developer other than its original author. With understandability comes readability, changeability, extensibility and maintainability.

General rules

Follow standard conventions.
Keep it simple stupid. Simpler is always better. Reduce complexity as much as possible.
Boy scout rule. Leave the campground cleaner than you found it.
Always find root cause. Always look for the root cause of a problem.

	singleuser:
	profileList:
	- display_name: "Default"
	description: \|
	Tubi Data Runtime
	default: True
	kubespawner_override:
	image: <private-docker-registry>/tubi-data-runtime
	node_affinity_preferred:
	- weight: 1

	<dependency>
	<groupId>org.springframework.boot</groupId>
	<artifactId>spring-boot-starter-rsocket</artifactId>
	<version>${spring-boot.version}</version>
	<exclusions>
	<exclusion>
	<groupId>io.netty</groupId>
	<artifactId>netty-buffer</artifactId>
	</exclusion>
	<exclusion>

	import org.openjdk.jmh.annotations.*;

	import java.util.Arrays;
	import java.util.Random;
	import java.util.concurrent.CountedCompleter;
	import java.util.concurrent.ExecutionException;

	/**
	* 40 Core Xeon E5-2660 v3 @ 2.60GHz
	*

	# wget -i this_file

	http://www.oreilly.com/programming/free/files/files/microservices-for-java-developers.pdf
	http://www.oreilly.com/programming/free/files/modern-java-ee-design-patterns.pdf
	http://www.oreilly.com/programming/free/files/object-oriented-vs-functional-programming.pdf
	http://www.oreilly.com/programming/free/files/java-the-legend.pdf
	http://www.oreilly.com/programming/free/files/functional-programming-python.pdf
	http://www.oreilly.com/programming/free/files/reactive-microservices-architecture-orm.pdf
	http://www.oreilly.com/programming/free/files/migrating-cloud-native-application-architectures.pdf
	http://www.oreilly.com/programming/free/files/software-architecture-patterns.pdf

	package examples;

	import org.springframework.boot.SpringApplication;
	import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
	import org.springframework.boot.autoconfigure.SpringBootApplication;

	@SpringBootApplication
	@EnableAutoConfiguration
	public class GatewayApplication {

	producer.initTransactions();
	try {
	producer.beginTransaction();
	producer.send(record1);
	producer.send(record2);
	producer.commitTransaction();
	} catch(ProducerFencedException e) {
	producer.close();
	} catch(KafkaException e) {
	producer.abortTransaction();