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01. PrefaceBrush Douban saw the third edition of in-depth understanding of JVM, so he bought it to update the JVM knowledge. This article is a note for personal Review only.02. Java memory area and memory overflow03. Runtime data area‍‍‍‍Reference: JVM specification, Memories of a Java RuntimeHeap: the memory area created by - Xmx, -Xms when th ...

Today, let's look at the capacity expansion mechanism of HashMap. It's hard to say in words. I'll try to make it clear. As long as we talk about the logic in resize, we can divide this method into two partsresize methodThis method mainly has two parts of logic. The first part is to set the size of the new array (newCap) and the threshold of the ...

java basic course virtual machine performance analysis and fault resolution tool [graphical interface] --------------Function: help judge problems such as high cpu occupancy, dead loop, deadlock, memory leak, memory overflow, etc.   ■ JConsole: focus on viewing threads and memory ■ VisualVM (recommended): it has the same function as JConsole, b ...

react source code analysis 13.hooks source codeVideo Explanation (efficient learning): Enter learningPrevious articles:1. Introduction and interview questions2. Design concept of react3.react source code architecture4. Source directory structure and debugging5. JSX & Core api6.legacy and concurrent mode entry functions7.Fiber architecture8. ...

leetcode essence of Dachang algorithm interview 20. String Video Explanation (efficient learning): Click to learn catalog: 1. Introduction 2. Time and space complexity 3. Dynamic planning 4. Greed 5. Binary search 6. Depth first & breadth first 7. Double pointer 8. Sliding window 9. Bit operation 10. Recursion & divide and conquer 11 Pr ...

redis setnx expiration time_ Several implementations of redis locking           We often encounter some problems such as repeated requests and concurrency in our work, and locking resources is a good means. Today, let's sort out several implementations of using redis as a distributed lock. redis can be used for several commands: I ...

Innodb of Innodb engine_ lock_ wait_ Timeout parameter description explain First, the Innodb engine will lock the corresponding row when executing the update statement and will not release it until the transaction is committed or rolled back. In the process of holding a row lock, if other transactions b also want to modify the data of the loc ...

for_each function for_each function is defined in the < algorithm > header file, and its function declaration is: template<class InputIt, class UnaryFunction> constexpr UnaryFunction for_each(InputIt first, InputIt last, UnaryFunction f) { for (; first != last; ++first) { f(*first); } return f; // implicit move s ...

1. Install ansible package [root@centos8 ~]yum -y install ansible 2. Modify profile ###Purpose: to cancel the error (yes/no) that occurs every time you connect to the remote host [root@centos8 ~]#vim /etc/ssh/ssh_config #Modify the following line StrictHostKeyChecking no perhaps [root@centos8 ~]#vim /etc/ansible/ansible.cfg Uncomment the ...

CentOS expansion volume grouppv, vg, lvPhysical volume (PV): refers to the hard disk partition, or the entire hard disk or the created soft RAID. It is the basic storage device of LVM.Volume group (VG): a storage pool composed of one or more physical volumes. One or more logical volumes can be created on the volume group.Logical volume (LV): si ...