数据库（MYSQL）运维要点 - 读书笔记


https://cloud.tencent.com/developer/article/1579285

 数据库复制技术

  • 异步复制  - 
    • 应用 发起更新 -->  Master 执行操作 ->  Master响应应用 ->  Master 向Slave 复制
  • 半同步复制
    • 应用 发起更新 -->  Master 执行操作 ->  Master 向Slave 复制 ->   slave接收数据 ->  Slave写到Relay Log里面，但不执行 -> Slave 响应Master  ->  Master响应应用 
  • 同步复制
    • 应用 发起更新 -->  Master 执行操作 ->  Master 向Slave 复制 ->   slave接收数据 ->  Slave执行更新 -> Slave 响应Master  ->  Master响应应用 
    • 至少两个Slave，来保证Slave高可用

高可用


binlog 日志用于记录所有更改数据的语句，俗称二进制日志，主要用于复制和即时点恢复。主从复制也是依赖于 binlog 的。类似于 Oracle 的 archivelog，Mongodb的oplog，所有和写有关或者可能有关的语句，都会记录在 binlog 文件中。


慢查询
慢查询就是执行数据库查询时消耗时间比较大的 SQL 语句。MySQL CPU 利用率过高，大部分原因与低效 SQL 有关系，通过优化低效 SQL 基本可以解决大部分问题。


Comments

Post a Comment

Popular posts from this blog

Small summery of ElasticSearch meetup

https://www.elastic.co/guide/en/elasticsearch/reference/current/_basic_concepts.html https://en.wikipedia.org/wiki/Document-oriented_database Configuration (a.k.a Design) matters a lot. Big performance impact to user. Design the configure based on the query pattern of users. Dual scoring model :  Bool query && ?? Shingles , 类似有pairwise，把一个句子里面的单词(token)没连续两个分组，比如 Hello the beautiful world -> [Hello the], [the beautiful], [beautiful world] Kopf:  https://github.com/lmenezes/elasticsearch-kopf, web admin page for elesticsearch
Read more

The trend in Test

Highlights: The programming skill of programmer are in general better than before.  Modern programming languages and frameworks make programmer potentially make less error.  Legacy system still lack of proper test, but the situation in many newly built system are better. Unit test and Integration test are paid more attentions, and in place.  The continuous integration and continuous deployment make the team the correct the error more fast and more often.  So if the team are confident can correct the defect within a short time, the formal manual test for the non-core function could be reduced.  But this is not true for safety or business critical product, which however only a very small part in the whole software industry.  The test need deeper domain knowledge and user knowledge to setup complex testcase.  Better architecture make the automation could be focus on the functional level, while the nature of frontend may not suitable for auto test ...
Read more

My review of EuroSTAR 2015 - Maastrict

Image
There are lot of great talks in EuroSTAR 2015.  I was really enjoy it, as well as the city Maastricht. Tidy, charming city with history, gourmet and exclusive shopping :) There are a few hot words into my ears. Autonomous management , self steer group.  DevOps is all about communication, collaboration, transparency.   Always start with WHY, follow with WHAT then HOW Continuous learning is the way to survival for tester.   Dedicate team, Automation in Agile.  Small team with B ig goal, leads to -> disruptive .  ************************************************************************** DevOps: My feel of DevOps is Collabration and Communcation.  To achieve efficiency, TA should be communication with different parities, get the needs from them ,and make the things happen. Open mind and fearless. [TU4].  Continuous Delivery means Continuous  Testing , but not means Continuous  Deployment  [TU4]. Communication ...
Read more