PG daemon - the first-class citizen process in the background is kept alive

pmdie/reaper/sigusr1_handler -> PostmasterStateMachine --> StartupDataBase ServerLoop(postmaster.c)/reaper/sigusr1_handler --> StartBackgroundWriter ServerLoop(postmaster.c)/reaper/PostmasterStateMachine/sigusr1_handler --> StartCheckpointer ServerLoop(postmaster.c)/reaper --> StartWalWriter ServerLoop(postmaster.c)/sigusr1_handl ...

Posted by judgy on Thu, 31 Mar 2022 18:43:32 +0300

Map + functional interface method to solve if else

Click to follow 👉   2022-01-25 10:33 659 source codes included in topic # taro Click "taro source code" above and select“ Set as star" Whether she's ahead or behind? A wave that can wave is a good wave! Update the article at 10:33 every day and lose 100 million hair every day Source code boutique column Orig ...

Posted by cgm225 on Thu, 31 Mar 2022 10:54:41 +0300

Using Redis in Spring

Using Redis in Spring 1. Configuration environment <!-- https://mvnrepository.com/artifact/redis.clients/jedis --> <dependency> <groupId>redis.clients</groupId> <artifactId>jedis</artifactId> <version>2.9.0</version> </dependency> <!-- https://mvnrepository.com/artifact/org.springf ...

Posted by xxreenaxx1 on Thu, 31 Mar 2022 09:43:00 +0300

What is OAuth2, the implementation of wechat login front and back, and Coding online

OAuth2 1, What problem does OAuth2 solve 1. Background of OAuth2 If the photo owner wants to print photos on the cloud printing service, the cloud printing service needs to access the resources on the cloud storage service 2. Legend Resource owner: Photo owner Customer application: cloud printing Protected resources: Photos 3. Method 1: ...

Posted by MytHunter on Thu, 31 Mar 2022 03:54:10 +0300

zset principle in Redis and implementation of jump table in Java

preparation First in Redis official website Download the latest stable version 6.2. Install on the Linux server according to the installation guide given on the official website. zadd calling procedure redis/src/server.c file defines the methods to be called by all commands. The zadd command calls t_zset.c file. struct redisCommand redisCom ...

Posted by Hillu on Wed, 30 Mar 2022 23:11:14 +0300

The function of nearby stores is realized in JAVA version

preface Recently, the company's project needs to realize the function of nearby stores. It is found that many methods can be realized by querying data. Including Mysql,Redis,Mongodb,PostgreSQL, etc redis and mongodb are selected for implementation. 1, Function of nearby stores redis implementation redis4. Version 0.14 uses the geo com ...

Posted by todd2006 on Wed, 30 Mar 2022 00:37:29 +0300

synchronized is no longer bloated. Put down the lightweight lock of his initial knowledge

preface Natural selection, survival of the fittest. JDK is also in constant optimization. As for the internal optimization of synchronized locks in JDK, we analyzed that biased locks are used to solve initial problems. With the continuous accumulation of competition, lightweight locks are produced.Pay attention to me, a progressive social anim ...

Posted by animedls on Mon, 28 Mar 2022 04:39:25 +0300

SpringBoot integrates Redis to serialize and store Java objects

After reading many articles, there are basically no more than two kinds of objects stored in Redis: convert the object into Json, and then deserialize it after taking it out, or convert the object into byte []. If you use spring boot, it may be easier to use spring data Redis. First, we use maven to build the Spring Boot project and introduce ...

Posted by phphunger on Mon, 28 Mar 2022 00:32:06 +0300

On the perfect scheme of Redission to realize distributed lock and Lua script

On the perfect scheme of Redission to realize distributed lock and Lua script preface In the previous article, I mentioned the redis distributed lock implementation and lua script related knowledge In some scenarios, multiple processes must monopolize and share resources in a mutually exclusive manner. At this time, distributed lockin ...

Posted by andreas on Sat, 26 Mar 2022 17:19:12 +0300