• Apiboot zero code integration spring security JDBC access token


    ApiBoot SecurityIn houseTwo waysRead the user information that needs to be authenticated, as mentioned in the previous articleApiBoot SecurityuseMemory modeDon’t write a single line of codeCan realize the user authentication and obtainAccessTokenThen we useJDBCIs the way so simple? If you’re still rightApiBootI don’t know. I can get help through the following ways. Official documents: http://apiboot.minbox.io […]

  • Memcached for multi structured data management


    Memcached for multi structured data management 1. Introduction to memcached Memcached is a high performanceDistributed memory objectsCache system is used for dynamic web application to reduce database load. Basic features: cache data and objects in memory to provide faster running speed for dynamic and database driven websites, so as to reduce the number of times […]

  • What are B-tree and B + tree in the series of data structure? Why can’t binary search trees work?


    This paper will introduce B-tree and B + tree. Firstly, it introduces the application scenario of B-tree and why B-tree is needed. Secondly, it introduces the query and insertion process of B-tree. Finally, it discusses the improvement of B + tree for B-tree.Before talking about B-tree, let’s talk about the application scenarios of B-tree. So […]

  • Linux monitoring system wgcloud, network topology


    Based on Java language, wgcloud is a high-performance and high concurrency distributed monitoring platform. The core modules include: server cluster monitoring, ES cluster monitoring, CPU monitoring, memory monitoring, data monitoring (mysql, Oracle, PG, etc.), service heartbeat detection, application process management, disk IO monitoring, system load monitoring, monitoring alarm information push.

  • What are the expiration policies of redis?


    We usually use memory as cache, but is memory infinite? Of course not. Memory is precious and limited. It is possible that a machine has more than ten gigabytes of memory, but it can hold a few tons of hard disk space. Reids mainly performs high-performance, high concurrency read-write operations based on memory. So here […]

  • Windows process communication


    In Windows program, each process often needs to exchange data and communicate with each other. Common methods are Using memory mapped files Share memory through shared memory DLL Send WM to another process using SendMessage_ COPYDATA message

  • Talking about the difference between equals and = =


    Talking about the difference between equals and = = 1Basic data type For the basic data, doubleStackThe data size is determined and the memory space can be allocated,They are stored directly by value, so they can be stored directlyAccess by value. The comparison between them directly selects = =, and here the direct comparison is […]

  • Remember a time to check the online program memory up and down, it is the big set caused trouble


    1: Background 1. Tell a story Yesterday, I continued to pay off the technical debt. After a round of optimization, the memory of the program continued to fluctuate from high to low, 20g at low, 30g at high, and then dropped several G after a while. No doubt, what set or operation in the program […]

  • JVM virtual machine GC


    GC During GC, the JVM does not recycle the three regions uniformly. Most of the recycling is in the new generation Cenozoic era From, to Old age There are two types of GC: light GC (normal GC) and heavy GC (Global GC) When an object has gone through GC for 15 times and has not […]

  • Does Python support copying strings?


    Several articles in a row were writing Python strings, which was unexpected to me. However, there are some problems that can’t be solved without writing, especially those problems that come up with a good idea. In the end, you find that,Many people don’t understand it at all, but they think they do。 Then go on […]

  • Memory management optimization (swstring)


    The latest optimization reduces the number ofrecv_bufferreachphp zvalMemory forcopyFromrecv_bufferBecomePHPLayeredstringType variable, equivalent to directly from theSocketRead in receive bufferPHPLayer. GitHub PR:https://github.com/swoole/swoole-src/pull/3423 Swstring structure typedef struct _swString { size_t length; size_t size; off_t offset; char *str; const swAllocator *allocator; } swString; In design, the functions of these fields are as follows: size: memory capacity lengthappendDuring the write […]

  • How much is the maximum memory of memory card


    What is the maximum memory of the memory card? We all want to know the answer to this question. We don’t count the fake ones. At present, the world’s largest capacity microSD card is Evo plus 256gb produced by Samsung! Recently, Samsung announced that it will sell a 256gb microSD card, which is also the […]