Tag:waiting time

  • MySQL disk IO too high


    The utilization rate of disk util% is 100%. First of all, it is suspected that it is caused by slow query statement. Check MySQL slow query mysql> show processlist; +——-+————-+———————+——+———+——–+—————————————————————————–+——————+ | Id | User | Host | db | Command | Time | State | Info | +——-+————-+———————+——+———+——–+—————————————————————————–+——————+ | 1 | system user | | […]

  • 23000 stars! Another GitHub query tool


    [introduction]: Sherlock is a tool to search social media accounts through user names on social networks. Why is it named after Sherlock Holmes. brief introduction Today is the Internet age, full of many social network systems, such as Zhihu, microblog, twitter, Facebook and so on. Using these social network sites, we need to establish our […]

  • Now there are three threads: T1, T2 and T3. How to ensure that T2 is executed after T1 and T3 is executed after T2


    Question: there are three threads: T1, T2 and T3. How do you ensure that T2 is executed after T1 and T3 is executed after T2 Implementation: using the join method in thread analysis: ThreadIn classjoinMethod is used to synchronize, the underlying is actually calledwaitmethod. Let’s take a look at the demo code package com.whh.concurrency; /** […]

  • Analysis of MySQL deadlock (intermediate)


    InnoDB actively detects the deadlock and rolls back a waiting transaction. The question is, how does InnoDB detect deadlocks?The intuitive method is that when two transactions wait for each other, when the waiting time of one transaction exceeds a set threshold, one transaction is rolled back, and the other transaction can continue to execute. This […]

  • App startup page optimization


    There are many app startup pages that are still the same splash activity, and then jump to mainactivity. First, splash loads the data once, and then it loads the data after entering main, so you have to wait for two loads. What if the reverse is true Here, mainactivity can be loaded first, and then […]

  • How to set Tomcat thread pool size?


    background In our daily development, we all use Tomcat as the server, but what size of thread pool should we set? And what are the principles for designing this thread pool? Next, I will introduce how I design and calculate. Specific methods As we all know, when Tomcat accepts a request, it will involve CPU […]

  • Illustrate the core data structure of kubernetes scheduler framework


    Framework is the second implementation of kubernetes extension. Compared with scheduleextender based on remote independent service, the framework core implements a localized standardized process management mechanism based on extension point 1. Expand to achieve the goal The design of the framework has been clearly described in the official documents. Currently, there is no stable. This […]

  • Apiping professional API management and automatic testing tool


    Function description Support multi team, multi project, multi environment, more in line with technology development and use scenarios Support API scenario group concurrent testing and performance testing Through the function authority and data authority, you can accurately control the user’s use right and make it in control Dynamic generation of API data, so that the […]

  • Three ways to write reworld waiting


    In the reworld editor, there are three ways to write the function of wait time: 1、 Process waiting In non code blocks, we can use the wait () function to wait directly In a function or loop, you need to use coroutine to wait coroutine.start(function()     …     coroutine.wait(1)     … end) 2、 Use timer timer local index = 0 local function hahalog() […]

  • Kafka source code analysis 2: metadata cluster meta information


    Summary As mentioned in the previous sectionClusterIt is mainly used to store node information, topicpartitionpartition information and partitioninfo partition details. This section is aboutMetadataWill beClusterEncapsulation provides a unified query entry, and also provides the update operation of cluster information. Class annotation By readingMetadataThe following conclusions can be drawn from the notes: Metadata is shared by […]