71 Matching Annotations
  1. Jun 2020
    1. 但优化过程中CS知识没涨,因为时间都花在和runtime玩上了

      这句话一下子就见高下了!

  2. Aug 2017
  3. Jul 2017
    1. local ok, err = red:connect("127.0.0.1", 6379)

      create a connection to redis server every time? is there anything like connection pool?

      the connect() method will always look up the connection pool for matched idle connections created by previous calls of this method.

      Instead of calling close(), call set_keepalive() to put current connection into the pool for next usage

    2. since lua-resty-redis can not be used in set_by_lua*, dynamic routing based on redis should be impelemented in the access_by_lua block

    1. 商业银行IT系统的开发演进基本跟随了软件技术的各个发展阶段

      主机/终端 -> C/S -> B/S, 3 Tiers, BI/CRM -> SOA

    1. 这张图给出了谷歌在2015年提出的Inception-v3模型。这个模型在ImageNet数据集上可以达到95%的正确率。然而,这个模型中有2500万个参数,分类一张图片需要50亿次加法或者乘法运算。

      95%成功率,需要 25,000,000个参数!

    1. the text after the ID doesn't matter. https://stackoverflow.com/questions/701030/ This is a great model for URLs where you want a to use a unique ID but the text/title in the URL may change.

      great design!

    1. 优雅高效的免费在线APP原型工具

      看着不错,有很多中国知名应用的现成样式组件可以引用

    1. a state machine or workflow. Trouble is, that's not what a Saga is. A Saga is a failure management pattern.

      Failure Management Pattern: good summary,

    2. Sagas come out of the realization that particularly long-lived transactions (originally even just inside databases), but also far distributed transactions across location and/or trust boundaries can't eaily be handled using the classic ACID model with 2-Phase commit and holding locks for the duration of the work. Instead, a Saga splits work into individual transactions whose effects can be, somehow, reversed after work has been performed and commited.

      focus on long-lived, far distributed transactions

    1. Everything you need to know about MQTTWe wrote this series to bring anybody up to speed with MQTT without requiring to read the whole MQTT specification. It explains the core of MQTT concepts, its features and other essential information.
    1. 目前RocketMQ最新的性能基准测试中,128字节小消息TPS已达47W
      1. QoS要求是什么?
      2. 具体物理机配置?
    2. 我们最终全部切换到了G1,16年双十一线上MetaQ集群采用的也是这一组参数,基本上GC时间能控制在20ms以内(一些超大的共享集群除外)。

      阿里在消息中间件中全部启用G1GC,从16年双十一就开始。这对G1GC是个不错的案例

  4. Jun 2017
    1. Quick Start Foundational Stack Here’s a handful of critical apps you’ll need to get any organization up and running quickly and cost effectively.

      using saas to boost your startup

    1. cool, it will show how many steps are needed to performce the regex! Greatful for tuning regex for performance

    1. It will then backtrack from the end until it reaches the first space.

      so greedy is evil? since it'll backtrack form the end!

    2. The faster you can throw out non-matching input, the fewer cycles you waste

      but in log analysis field, almost every line are machted, we'just want to use regex to extract fields inside the line. Is the "the longer the better" still matter?

    1. Character classes Possessive quantifiers (and atomic groups) Lazy quantifiers Anchors and boundaries Optimizing regex order
    1. internal dsl in java 8 in three ways:

      1. by Method Chaining
      2. by Nested Functions
      3. by Lambda Expression
    1. I’m not entitled to have an opinion unless I can state the arguments agains my position better than the people who are in opposition. I think that I am qualified to speak only when I’ve reached that state.

      做架构设计也是这样,每个决定都是取舍,最起码要有能力提出反对自己决定的强力观点

    1. 华为的Li Zefan同学

      之前在富士通南大就做Linux Kernel开发,后来到华为

    2. Linux CGroup全称Linux Control Group, 是Linux内核的一个功能,用来限制,控制与分离一个进程组群的资源(如CPU、内存、磁盘输入输出等)。

      关键是cpu

    1. How often have we not seen an SOA initiative slowed down by conflicts between service providers and service consumers on what constitutes a good service interface? On the one side a mobile developer just wants it to be simple for their particular app, on the other side the backend team wants everyone to use the same standardized service and data model.

      SOA: A stable interface for all consumers

      API: Particular API for particular needs

    2. APIs are controlled (proxy) views on the data and capabilities of a domain, optimized for the needs of the API consumer.

      So API should be more cheaper to create and maintaion than Services