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System design DDIA digest - 5. Replication
5. ReplicationReplication means: keep a copy of data on multiple machines. geographicly close to users to reduce latency increase availability even if one machine is down increase read throughputreplication algorithm: single-leader replication...…
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Regression Newman with HTML report
Regression Report with NewMan#!/bin/bashcd $(dirname $0)ENV=${1:-QA}echo "Testing $ENV environment."[ ! -d newman ] && mkdir newman[ -d newman/newman ] && rm newman/newman/xxx-regression-*.htmlcd newman || exitexport PATH=/devops/t...…
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Flask introduction & set up
Set up env (virtual environment)tutorial$ python -m venv env # Windows$ python3 -m venv env # Linux or macOSIn python, there is no central lib management tools like Maven in Java, and it is not possible to have different version of same lib, so ...…
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Dead Letter Queue(DLQ) Handler Service
Dead Letter QueueA Dead Letter Queue (DLQ) is a service implementation utilised in message-based systems to store messages that could not be processed or delivered.For consumer, there may be scenarios in which incoming messages cannot be fully pro...…
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Debug in distributed system (Splunk)
SplunkSplunkindex=application_na sourcetype=fs_newarch_qa source=*gfs-feaid-services*Response Time: index=application_na sourcetype=fs_newarch_prod source=*fs-utilities* eventType=END OR eventType=ERROR | timechart avg(duration)tps:index=applicat...…
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Failure detection and handling in distributed system
Failure detectionIn distributed system, it requires at least two independent sources of information to mark a server dowm. One server is not enough. (It’s not enough to simply say because your node can’t contact another node that the other node is...…
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Kafka Basic
Kafka recordan events contains: value: required key: used to determine partition timestamp: order message headers: store HTTP headers and metadatamessage store processtwo-steps:Partition Determination: message –hash(key)–> partition (preser...…
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System design Basic - scale up system
Scale Route1. Single server2. Database (separate Data tier and web traffic tier)Choose which database to use, Nosql or relational databaseNon-relational database might be the right choice if (easy to scale, no join operations): app requires super...…
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kafka & redis
Kafka & Redis cacheKafka Workflow(Two type of events: bulk load & change data) DB2 mainframe | retrieve data bulk load | ...…
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OOD learning
OODmanagement system OODGym, Parking lot, Hotel, Library, Restaurant, etc.When get the problem, think about if there is a management role in the system. If yes, it belongs to management system.This kind of questions are frequently asked in intervi...…
