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1, Performance optimization analysis The execution of a computing task mainly depends on CPU, memory and bandwidth. Spark is a memory based computing engine, so for it, the biggest impact may be memory. Generally, our tasks encounter performance bottlenecks, and most of them are memory problems. Of course, CPU and bandwidth may also affect th ...

Starting portal: https://ssshooter.com/2021-03...Split componentI also thought that dismantling molecular components was used for abstraction, but practice told me that dismantling molecular components was a way to improve performance (specific situation).I have encountered such a problem in my actual work. There is a large table with multiple ...

1, Memory pool introduction 1. Introduction to C + + memory pool Memory pool is a kind of memory allocation method. It is to apply for allocating a certain number of memory blocks of equal size (generally) for standby before using memory. When there is a new memory demand, a part of the memory block is separated from the memory pool. If the m ...

Article from personal blog: https://knightyun.github.io/2021/05/09/js-react-purecomponent , reprint, please state In the React class component, if the state changes, it will trigger the re rendering of the component (execute the render method), and it is all re rendering including all sub components, whether some sub components use the value ...

preface In Android, memory leakage is very common; The consequences of memory leakage will make the application Crash This article comprehensively introduces the essence, causes and solutions of memory leakage, and finally provides some common memory leakage analysis tools. I hope you will like them. catalogue 1.png 1. Introduction ML (M ...

preface The difference between ArrayList and LinkedList is often mentioned. A clear understanding of the difference between them is helpful to consolidate their basic development skills. Choosing the right data structure in the right place can help them write more high-quality code. Combined with their source code, this paper analyzes th ...

Index optimization and query optimization 1, Data preparation Insert 500000 entries in the student table and 10000 entries in the class table. Step 1: create a table #Class table CREATE TABLE `class` ( `id` INT(11) NOT NULL AUTO_INCREMENT, `className` VARCHAR(30) DEFAULT NULL, `address` VARCHAR(40) DEFAULT NULL, `monitor` INT NULL , PRIMARY ...

catalogue Disk performance index Attention Usage scenario Performance testing tool fio Disk I/O observation Interpretation of iostat index ​ Process I/O observation pidstat iotop Question How to determine whether it is random io or sequential io? Disk performance index Utilization, saturation, IOPS, throughput, response time, etc ...

1, Introduce As a large memory consumer, pictures have always been the key object that developers try to optimize. Bitmap's memory is located in native before 3.0, then changed to jvm, and then changed back to native after 8.0. Each jvm process has a memory limit, while native has no limit (not without impact, at least not oom). Therefore, mov ...

preface Spark job optimization is actually a general topic, because sometimes it is slow, but the solution is really different. I want to point out all aspects of optimization so that the system can formulate the overall optimization scheme. Sorting out optimization ideas How to treat the so-called slow problem? I made a sorting: themeresou ...