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In this tutorial, we are going to learn how to install MySQL community server on Mac and setting up the MySQL in Terminal app.
Mac OS doesn’t come along with the pre-configured version of MySQL, but this step by step guide will make the task easy for you. By the end of this tutorial, you will be able to set up the MySQL server on your Mac system for local development purposes.
Before we start installing MySQL server on mac, we first download the latest version of MySQL from its official site. Visit https://dev.mysql.com/downloads/mysql and choose the MySQL version that you want to download.
On this page, you will see list of operating systems under the “Select Operating System” dropdown choose the macOS from the list. Then, click on the download button for the MySQL .dmg file. You can download the other MySQL instances as per your operating system requirement.
#mysql
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HTML to Markdown
MySQL is the all-time number one open source database in the world, and a staple in RDBMS space. DigitalOcean is quickly building its reputation as the developers cloud by providing an affordable, flexible and easy to use cloud platform for developers to work with. MySQL on DigitalOcean is a natural fit, but what’s the best way to deploy your cloud database? In this post, we are going to compare the top two providers, DigitalOcean Managed Databases for MySQL vs. ScaleGrid MySQL hosting on DigitalOcean.
At a glance – TLDR
ScaleGrid Blog - At a glance overview - 1st pointCompare Throughput
ScaleGrid averages almost 40% higher throughput over DigitalOcean for MySQL, with up to 46% higher throughput in write-intensive workloads. Read now
ScaleGrid Blog - At a glance overview - 2nd pointCompare Latency
On average, ScaleGrid achieves almost 30% lower latency over DigitalOcean for the same deployment configurations. Read now
ScaleGrid Blog - At a glance overview - 3rd pointCompare Pricing
ScaleGrid provides 30% more storage on average vs. DigitalOcean for MySQL at the same affordable price. Read now
MySQL DigitalOcean Performance Benchmark
In this benchmark, we compare equivalent plan sizes between ScaleGrid MySQL on DigitalOcean and DigitalOcean Managed Databases for MySQL. We are going to use a common, popular plan size using the below configurations for this performance benchmark:
Comparison Overview
ScaleGridDigitalOceanInstance TypeMedium: 4 vCPUsMedium: 4 vCPUsMySQL Version8.0.208.0.20RAM8GB8GBSSD140GB115GBDeployment TypeStandaloneStandaloneRegionSF03SF03SupportIncludedBusiness-level support included with account sizes over $500/monthMonthly Price$120$120
As you can see above, ScaleGrid and DigitalOcean offer the same plan configurations across this plan size, apart from SSD where ScaleGrid provides over 20% more storage for the same price.
To ensure the most accurate results in our performance tests, we run the benchmark four times for each comparison to find the average performance across throughput and latency over read-intensive workloads, balanced workloads, and write-intensive workloads.
Throughput
In this benchmark, we measure MySQL throughput in terms of queries per second (QPS) to measure our query efficiency. To quickly summarize the results, we display read-intensive, write-intensive and balanced workload averages below for 150 threads for ScaleGrid vs. DigitalOcean MySQL:
ScaleGrid MySQL vs DigitalOcean Managed Databases - Throughput Performance Graph
For the common 150 thread comparison, ScaleGrid averages almost 40% higher throughput over DigitalOcean for MySQL, with up to 46% higher throughput in write-intensive workloads.
#cloud #database #developer #digital ocean #mysql #performance #scalegrid #95th percentile latency #balanced workloads #developers cloud #digitalocean droplet #digitalocean managed databases #digitalocean performance #digitalocean pricing #higher throughput #latency benchmark #lower latency #mysql benchmark setup #mysql client threads #mysql configuration #mysql digitalocean #mysql latency #mysql on digitalocean #mysql throughput #performance benchmark #queries per second #read-intensive #scalegrid mysql #scalegrid vs. digitalocean #throughput benchmark #write-intensive
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Background Fetch is a very simple plugin which attempts to awaken an app in the background about every 15 minutes, providing a short period of background running-time. This plugin will execute your provided callbackFn
whenever a background-fetch event occurs.
There is no way to increase the rate which a fetch-event occurs and this plugin sets the rate to the most frequent possible — you will never receive an event faster than 15 minutes. The operating-system will automatically throttle the rate the background-fetch events occur based upon usage patterns. Eg: if user hasn't turned on their phone for a long period of time, fetch events will occur less frequently or if an iOS user disables background refresh they may not happen at all.
:new: Background Fetch now provides a scheduleTask
method for scheduling arbitrary "one-shot" or periodic tasks.
scheduleTask
seems only to fire when the device is plugged into power.stopOnTerminate: false
for iOS.@config enableHeadless
)⚠️ If you have a previous version of react-native-background-fetch < 2.7.0
installed into react-native >= 0.60
, you should first unlink
your previous version as react-native link
is no longer required.
$ react-native unlink react-native-background-fetch
yarn
$ yarn add react-native-background-fetch
npm
$ npm install --save react-native-background-fetch
react-native >= 0.60
react-native >= 0.60
ℹ️ This repo contains its own Example App. See /example
import React from 'react';
import {
SafeAreaView,
StyleSheet,
ScrollView,
View,
Text,
FlatList,
StatusBar,
} from 'react-native';
import {
Header,
Colors
} from 'react-native/Libraries/NewAppScreen';
import BackgroundFetch from "react-native-background-fetch";
class App extends React.Component {
constructor(props) {
super(props);
this.state = {
events: []
};
}
componentDidMount() {
// Initialize BackgroundFetch ONLY ONCE when component mounts.
this.initBackgroundFetch();
}
async initBackgroundFetch() {
// BackgroundFetch event handler.
const onEvent = async (taskId) => {
console.log('[BackgroundFetch] task: ', taskId);
// Do your background work...
await this.addEvent(taskId);
// IMPORTANT: You must signal to the OS that your task is complete.
BackgroundFetch.finish(taskId);
}
// Timeout callback is executed when your Task has exceeded its allowed running-time.
// You must stop what you're doing immediately BackgroundFetch.finish(taskId)
const onTimeout = async (taskId) => {
console.warn('[BackgroundFetch] TIMEOUT task: ', taskId);
BackgroundFetch.finish(taskId);
}
// Initialize BackgroundFetch only once when component mounts.
let status = await BackgroundFetch.configure({minimumFetchInterval: 15}, onEvent, onTimeout);
console.log('[BackgroundFetch] configure status: ', status);
}
// Add a BackgroundFetch event to <FlatList>
addEvent(taskId) {
// Simulate a possibly long-running asynchronous task with a Promise.
return new Promise((resolve, reject) => {
this.setState(state => ({
events: [...state.events, {
taskId: taskId,
timestamp: (new Date()).toString()
}]
}));
resolve();
});
}
render() {
return (
<>
<StatusBar barStyle="dark-content" />
<SafeAreaView>
<ScrollView
contentInsetAdjustmentBehavior="automatic"
style={styles.scrollView}>
<Header />
<View style={styles.body}>
<View style={styles.sectionContainer}>
<Text style={styles.sectionTitle}>BackgroundFetch Demo</Text>
</View>
</View>
</ScrollView>
<View style={styles.sectionContainer}>
<FlatList
data={this.state.events}
renderItem={({item}) => (<Text>[{item.taskId}]: {item.timestamp}</Text>)}
keyExtractor={item => item.timestamp}
/>
</View>
</SafeAreaView>
</>
);
}
}
const styles = StyleSheet.create({
scrollView: {
backgroundColor: Colors.lighter,
},
body: {
backgroundColor: Colors.white,
},
sectionContainer: {
marginTop: 32,
paddingHorizontal: 24,
},
sectionTitle: {
fontSize: 24,
fontWeight: '600',
color: Colors.black,
},
sectionDescription: {
marginTop: 8,
fontSize: 18,
fontWeight: '400',
color: Colors.dark,
},
});
export default App;
In addition to the default background-fetch task defined by BackgroundFetch.configure
, you may also execute your own arbitrary "oneshot" or periodic tasks (iOS requires additional Setup Instructions). However, all events will be fired into the Callback provided to BackgroundFetch#configure
:
scheduleTask
on iOS seems only to run when the device is plugged into power.scheduleTask
on iOS are designed for low-priority tasks, such as purging cache files — they tend to be unreliable for mission-critical tasks. scheduleTask
will never run as frequently as you want.fetch
event is much more reliable and fires far more often.scheduleTask
on iOS stop when the user terminates the app. There is no such thing as stopOnTerminate: false
for iOS.// Step 1: Configure BackgroundFetch as usual.
let status = await BackgroundFetch.configure({
minimumFetchInterval: 15
}, async (taskId) => { // <-- Event callback
// This is the fetch-event callback.
console.log("[BackgroundFetch] taskId: ", taskId);
// Use a switch statement to route task-handling.
switch (taskId) {
case 'com.foo.customtask':
print("Received custom task");
break;
default:
print("Default fetch task");
}
// Finish, providing received taskId.
BackgroundFetch.finish(taskId);
}, async (taskId) => { // <-- Task timeout callback
// This task has exceeded its allowed running-time.
// You must stop what you're doing and immediately .finish(taskId)
BackgroundFetch.finish(taskId);
});
// Step 2: Schedule a custom "oneshot" task "com.foo.customtask" to execute 5000ms from now.
BackgroundFetch.scheduleTask({
taskId: "com.foo.customtask",
forceAlarmManager: true,
delay: 5000 // <-- milliseconds
});
API Documentation
@param {Integer} minimumFetchInterval [15]
The minimum interval in minutes to execute background fetch events. Defaults to 15
minutes. Note: Background-fetch events will never occur at a frequency higher than every 15 minutes. Apple uses a secret algorithm to adjust the frequency of fetch events, presumably based upon usage patterns of the app. Fetch events can occur less often than your configured minimumFetchInterval
.
@param {Integer} delay (milliseconds)
ℹ️ Valid only for BackgroundFetch.scheduleTask
. The minimum number of milliseconds in future that task should execute.
@param {Boolean} periodic [false]
ℹ️ Valid only for BackgroundFetch.scheduleTask
. Defaults to false
. Set true to execute the task repeatedly. When false
, the task will execute just once.
@config {Boolean} stopOnTerminate [true]
Set false
to continue background-fetch events after user terminates the app. Default to true
.
@config {Boolean} startOnBoot [false]
Set true
to initiate background-fetch events when the device is rebooted. Defaults to false
.
❗ NOTE: startOnBoot
requires stopOnTerminate: false
.
@config {Boolean} forceAlarmManager [false]
By default, the plugin will use Android's JobScheduler
when possible. The JobScheduler
API prioritizes for battery-life, throttling task-execution based upon device usage and battery level.
Configuring forceAlarmManager: true
will bypass JobScheduler
to use Android's older AlarmManager
API, resulting in more accurate task-execution at the cost of higher battery usage.
let status = await BackgroundFetch.configure({
minimumFetchInterval: 15,
forceAlarmManager: true
}, async (taskId) => { // <-- Event callback
console.log("[BackgroundFetch] taskId: ", taskId);
BackgroundFetch.finish(taskId);
}, async (taskId) => { // <-- Task timeout callback
// This task has exceeded its allowed running-time.
// You must stop what you're doing and immediately .finish(taskId)
BackgroundFetch.finish(taskId);
});
.
.
.
// And with with #scheduleTask
BackgroundFetch.scheduleTask({
taskId: 'com.foo.customtask',
delay: 5000, // milliseconds
forceAlarmManager: true,
periodic: false
});
@config {Boolean} enableHeadless [false]
Set true
to enable React Native's Headless JS mechanism, for handling fetch events after app termination.
index.js
(MUST BE IN index.js
):import BackgroundFetch from "react-native-background-fetch";
let MyHeadlessTask = async (event) => {
// Get task id from event {}:
let taskId = event.taskId;
let isTimeout = event.timeout; // <-- true when your background-time has expired.
if (isTimeout) {
// This task has exceeded its allowed running-time.
// You must stop what you're doing immediately finish(taskId)
console.log('[BackgroundFetch] Headless TIMEOUT:', taskId);
BackgroundFetch.finish(taskId);
return;
}
console.log('[BackgroundFetch HeadlessTask] start: ', taskId);
// Perform an example HTTP request.
// Important: await asychronous tasks when using HeadlessJS.
let response = await fetch('https://reactnative.dev/movies.json');
let responseJson = await response.json();
console.log('[BackgroundFetch HeadlessTask] response: ', responseJson);
// Required: Signal to native code that your task is complete.
// If you don't do this, your app could be terminated and/or assigned
// battery-blame for consuming too much time in background.
BackgroundFetch.finish(taskId);
}
// Register your BackgroundFetch HeadlessTask
BackgroundFetch.registerHeadlessTask(MyHeadlessTask);
@config {integer} requiredNetworkType [BackgroundFetch.NETWORK_TYPE_NONE]
Set basic description of the kind of network your job requires.
If your job doesn't need a network connection, you don't need to use this option as the default value is BackgroundFetch.NETWORK_TYPE_NONE
.
NetworkType | Description |
---|---|
BackgroundFetch.NETWORK_TYPE_NONE | This job doesn't care about network constraints, either any or none. |
BackgroundFetch.NETWORK_TYPE_ANY | This job requires network connectivity. |
BackgroundFetch.NETWORK_TYPE_CELLULAR | This job requires network connectivity that is a cellular network. |
BackgroundFetch.NETWORK_TYPE_UNMETERED | This job requires network connectivity that is unmetered. Most WiFi networks are unmetered, as in "you can upload as much as you like". |
BackgroundFetch.NETWORK_TYPE_NOT_ROAMING | This job requires network connectivity that is not roaming (being outside the country of origin) |
@config {Boolean} requiresBatteryNotLow [false]
Specify that to run this job, the device's battery level must not be low.
This defaults to false. If true, the job will only run when the battery level is not low, which is generally the point where the user is given a "low battery" warning.
@config {Boolean} requiresStorageNotLow [false]
Specify that to run this job, the device's available storage must not be low.
This defaults to false. If true, the job will only run when the device is not in a low storage state, which is generally the point where the user is given a "low storage" warning.
@config {Boolean} requiresCharging [false]
Specify that to run this job, the device must be charging (or be a non-battery-powered device connected to permanent power, such as Android TV devices). This defaults to false.
@config {Boolean} requiresDeviceIdle [false]
When set true, ensure that this job will not run if the device is in active use.
The default state is false: that is, the for the job to be runnable even when someone is interacting with the device.
This state is a loose definition provided by the system. In general, it means that the device is not currently being used interactively, and has not been in use for some time. As such, it is a good time to perform resource heavy jobs. Bear in mind that battery usage will still be attributed to your application, and shown to the user in battery stats.
Method Name | Arguments | Returns | Notes |
---|---|---|---|
configure | {FetchConfig} , callbackFn , timeoutFn | Promise<BackgroundFetchStatus> | Configures the plugin's callbackFn and timeoutFn . This callback will fire each time a background-fetch event occurs in addition to events from #scheduleTask . The timeoutFn will be called when the OS reports your task is nearing the end of its allowed background-time. |
scheduleTask | {TaskConfig} | Promise<boolean> | Executes a custom task. The task will be executed in the same Callback function provided to #configure . |
status | callbackFn | Promise<BackgroundFetchStatus> | Your callback will be executed with the current status (Integer) 0: Restricted , 1: Denied , 2: Available . These constants are defined as BackgroundFetch.STATUS_RESTRICTED , BackgroundFetch.STATUS_DENIED , BackgroundFetch.STATUS_AVAILABLE (NOTE: Android will always return STATUS_AVAILABLE ) |
finish | String taskId | Void | You MUST call this method in your callbackFn provided to #configure in order to signal to the OS that your task is complete. iOS provides only 30s of background-time for a fetch-event -- if you exceed this 30s, iOS will kill your app. |
start | none | Promise<BackgroundFetchStatus> | Start the background-fetch API. Your callbackFn provided to #configure will be executed each time a background-fetch event occurs. NOTE the #configure method automatically calls #start . You do not have to call this method after you #configure the plugin |
stop | [taskId:String] | Promise<boolean> | Stop the background-fetch API and all #scheduleTask from firing events. Your callbackFn provided to #configure will no longer be executed. If you provide an optional taskId , only that #scheduleTask will be stopped. |
BGTaskScheduler
API for iOS 13+[||]
button to initiate a Breakpoint.(lldb)
, paste the following command (Note: use cursor up/down keys to cycle through previously run commands):e -l objc -- (void)[[BGTaskScheduler sharedScheduler] _simulateLaunchForTaskWithIdentifier:@"com.transistorsoft.fetch"]
[ > ]
button to continue. The task will execute and the Callback function provided to BackgroundFetch.configure
will receive the event.BGTaskScheduler
api supports simulated task-timeout events. To simulate a task-timeout, your fetchCallback
must not call BackgroundFetch.finish(taskId)
:let status = await BackgroundFetch.configure({
minimumFetchInterval: 15
}, async (taskId) => { // <-- Event callback.
// This is the task callback.
console.log("[BackgroundFetch] taskId", taskId);
//BackgroundFetch.finish(taskId); // <-- Disable .finish(taskId) when simulating an iOS task timeout
}, async (taskId) => { // <-- Event timeout callback
// This task has exceeded its allowed running-time.
// You must stop what you're doing and immediately .finish(taskId)
print("[BackgroundFetch] TIMEOUT taskId:", taskId);
BackgroundFetch.finish(taskId);
});
e -l objc -- (void)[[BGTaskScheduler sharedScheduler] _simulateExpirationForTaskWithIdentifier:@"com.transistorsoft.fetch"]
BackgroundFetch
APIDebug->Simulate Background Fetch
$ adb logcat
:$ adb logcat *:S ReactNative:V ReactNativeJS:V TSBackgroundFetch:V
21+
:$ adb shell cmd jobscheduler run -f <your.application.id> 999
<21
, simulate a "Headless JS" event with (insert <your.application.id>)$ adb shell am broadcast -a <your.application.id>.event.BACKGROUND_FETCH
Download Details:
Author: transistorsoft
Source Code: https://github.com/transistorsoft/react-native-background-fetch
License: MIT license
1618900707
MySQL configuration variables are a set of server system variables used to configure the operation and behavior of the server. In this blog post, we will explain the differences in managing the configuration variables between MySQL 5.7 and MySQL 8.0.
We will explain three different ways for setting the configuration variables based on your use-case. Configuration variables that can be set at run time are called Dynamic variables and those that need a MySQL server restart to take effect are called Non-Dynamic variables.
#mysql #mysql 5.7 #mysql 8.0 #mysql server
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MySQL configuration variables are a set of server system variables used to configure the operation and behavior of the server. In this blog post, we will explain the differences in managing the configuration variables between MySQL 5.7 and MySQL 8.0.
We will explain three different ways for setting the configuration variables based on your use-case. Configuration variables that can be set at run-time are called Dynamic variables and those that need a MySQL server restart to take effect are called Non-Dynamic variables.
#mysql #mysql 5.7 #mysql server #mysql 8.0
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MySQL does not limit the number of slaves that you can connect to the master server in a replication topology. However, as the number of slaves increases, they will have a toll on the master resources because the binary logs will need to be served to different slaves working at different speeds. If the data churn on the master is high, the serving of binary logs alone could saturate the network interface of the master.
A classic solution for this problem is to deploy a binlog server – an intermediate proxy server that sits between the master and its slaves. The binlog server is set up as a slave to the master, and in turn, acts as a master to the original set of slaves. It receives binary log events from the master, does not apply these events, but serves them to all the other slaves. This way, the load on the master is tremendously reduced, and at the same time, the binlog server serves the binlogs more efficiently to slaves since it does not have to do any other database server processing.
Ripple is an open source binlog server developed by Pavel Ivanov. A blog post from Percona, titled MySQL Ripple: The First Impression of a MySQL Binlog Server, gives a very good introduction to deploying and using Ripple. I had an opportunity to explore Ripple in some more detail and wanted to share my observations through this post.
Ripple supports only GTID mode, and not file and position-based replication. If your master is running in non-GTID mode, you will get this error from Ripple:
Failed to read packet: Got error reading packet from server: The replication sender thread cannot start in AUTO_POSITION mode: this server has GTID_MODE = OFF instead of ON.
You can specify Server_id and UUID for the ripple server using the cmd line options: -ripple_server_id and -ripple_server_uuid
Both are optional parameters, and if not specified, Ripple will use the default server_id=112211 and uuid will be auto generated.
While connecting to the master, you can specify the replication user and password using the command line options:
-ripple_master_user and -ripple_master_password
You can use the command line options -ripple_server_ports and -ripple_server_address to specify the connection end points for the Ripple server. Ensure to specify the network accessible hostname or IP address of your Ripple server as the -rippple_server_address. Otherwise, by default, Ripple will bind to localhost and hence you will not be able to connect to it remotely.
You can use the CHANGE MASTER TO command to connect your slaves to replicate from the Ripple server.
To ensure that Ripple can authenticate the password that you use to connect to it, you need to start Ripple by specifying the option -ripple_server_password_hash
For example, if you start the ripple server with the command:
rippled -ripple_datadir=./binlog_server -ripple_master_address= <master ip> -ripple_master_port=3306 -ripple_master_user=repl -ripple_master_password='password' -ripple_server_ports=15000 -ripple_server_address='172.31.23.201' -ripple_server_password_hash='EF8C75CB6E99A0732D2DE207DAEF65D555BDFB8E'
you can use the following CHANGE MASTER TO command to connect from the slave:
CHANGE MASTER TO master_host='172.31.23.201', master_port=15000, master_password=’XpKWeZRNH5#satCI’, master_user=’rep’
Note that the password hash specified for the Ripple server corresponds to the text password used in the CHANGE MASTER TO command. Currently, Ripple does not authenticate based on the usernames and accepts any non-empty username as long as the password matches.
Exploring MySQL Binlog Server - Ripple
It’s possible to monitor and manage the Ripple server using the MySQL protocol from any standard MySQL client. There are a limited set of commands that are supported which you can see directly in the source code on the mysql-ripple GitHub page.
Some of the useful commands are:
SELECT @@global.gtid_executed;
– To see the GTID SET of the Ripple server based on its downloaded binary logs.STOP SLAVE;
– To disconnect the Ripple server from the master.START SLAVE;
– To connect the Ripple server to the master.#cloud #database #developer #high availability #mysql #performance #binary logs #gtid replication #mysql binlog #mysql protocol #mysql ripple #mysql server #parallel threads #proxy server #replication topology #ripple server