• Solution of [cache penetration, cache breakdown, cache avalanche] in redis cache


    1. Preface When we design a redis cache service, we have to consider three issues: cache penetration, cache breakdown and cache avalanche. At the same time, the interviewer will often ask these three questions. In this chapter, we will analyze these three problems. 2. Cache penetration 2.1 what is cache penetration? Under normal circumstances, query […]

  • Interview was asked, 10 million integers to quickly find an integer, how would you do?


      Launched on personal website:Interview was asked, 10 million integers to quickly find an integer, how would you do?   Recently, Xiao Lin was asked such an interesting question in his job interview Suppose that we need to quickly find out whether an integer exists in 10 million integers (the range of integers is between […]

  • “Advanced” Bloom filter is enough


    preface It’s enough in the article “friction interviewer” redis. It’s mentioned that bloom filter is used to solve cache penetration. Well, today, he’s here, he’s here, he’s here with colorful auspicious clouds What is it? Freire droid’s heart bloom is a hero in lol. now I’ll introduce his skills and costumes to you. At this […]

  • Jingtao project day15


    Cgb2010 Jingtao project day15 1. Redis cluster See notes for details 1.1 redis cluster outage conditions Outage condition: when the host in redis is missing, and there is no slave replacement, redis memory data is lost. At this time, redis cluster crashes Problem 1: 6 redis 3 masters and 3 slaves (1 master and 1 […]

  • From cache penetration to bloom filter


    Cache is now widely used in the web field, I believe most developers will use it, but have you ever met cache penetration? What is cache penetration? Cache penetration refers to querying a data that does not exist at all. Both the cache layer and the storage layer will not hit. However, for the sake […]

  • Flink mass data De duplication scheme


    preface Data duplication is a common problem in our big data siege lion. In addition to the traditional usage such as statistical UV, the significance of de duplication is to eliminate the influence of dirty data generated by unreliable data sources, that is, repeatedly reported data or repeatedly delivered data, so as to make the […]

  • [actual combat problem] – bloom filter of cache penetration (1)


    As mentioned earlier, in the case of preventing cache penetration (CACHE penetration refers to,Data that neither cache nor database hasFor example, the order number cannot be-1, but the user requested a large number of-1Because the data does not exist, the cache will not exist, and all requests will directly penetrate into the database. ), we […]

  • Bloom filter based on PHP + redis


    Since redis implements setbit and getbit operations, it is naturally suitable to implement bloom filter. Redis also has bloom filter plug-in. Here, we use PHP + redis to implement the bloom filter. First of all, define a hash function set class. These hash functions are not necessarily used. In fact, three 32-bit hash values are […]

  • Discussion on Bloom filter (1)


    Let’s talk about bloom filter today. Bloom filter was proposed by bloom, Burton h. in 1970. Bloom filter is a data structure used to support membership query.In short, bloom filter is used to test whether an element is a member of a given data set. The bloom filter has the following features: *Compared with the […]

  • Discussion on Bloom filter (2)


    Then I will continue to talk about the application of Bloom filter in Oracle database. Oracle database uses bloom filter in the following scenarios: Reduce the data traffic between slave processes in parallel join. ※1 Implement connection filter pruning. ※2 Support result caching. ※3 ※1:available from Oracle Database 10g Release 2※2:available from Oracle Database 11g […]

  • One article teaches you to understand cache breakdown, penetration, avalanche, degradation, etc


    For caching, we are certainly not unfamiliar, whether it is front-end or server-side development, caching is almost one of the essential optimization methods. In the actual production environment, the use of cache specification has been attached great importance. If it is not used well, it is easy to encounter serious abnormal scenarios such as cache […]

  • Hard core, handwritten bloom filter (with algorithm flow chart)


    preface Cache penetration concept When you query a certain nonexistent data, because of cache miss, you can’t find the result by querying the database, so it won’t be written to the cache. This will cause every query to request the database, resulting in cache penetration. Solution: Bloom filter stores all possible query parameters in hash […]