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Introduction to OLTP-Bench OLTP-Bench is an open-source benchmarking tool platform for OLTP scenarios from CMU’s DB Group. It was designed to provide a simple, easy-to-use, and extensible testing platform. It connects to databases via the JDBC interface, supporting the following test suites: TPC-C Wikipedia Synthetic Resource Stresser Twitter Epinions.com TATP AuctionMark SEATS YCSB JPAB (Hibernate) CH-benCHmark Voter (Japanese “American Idol”) SIBench (Snapshot Isolation) SmallBank LinkBench Detailed project information can be found here, and the GitHub page is here. ...

Background The English font set in Microsoft’s VS Code is monospaced, while the Chinese font is not. Method Download and install the fonts from here. This font combines Source Han Sans and is said to align punctuation strictly. Use the method described here to set up VS Code. PS: It is indeed aligned, although the English text appears a bit narrow.

Background The DDL paper on F1 serves as the foundation for TiDB’s DDL implementation. There are two main papers on F1: one provides an overview of F1’s DDL, and the other specifically details the schema change method for DDL. I personally believe the second is key and more confusing to me. There is an introduction to the second paper here, which can help in understanding. Understanding Online DDL Concept The DDL discussed here refers to online DDL. The concept of online DDL originates from databases like MySQL, whereas PostgreSQL and similar databases might not support it. This concept is also quite vague; the distinction is whether you need to use exclusive locks during DDL operations to block transactions. Therefore, all databases can perform online DDL; it just depends on whether they’re willing to put in the effort. For traditional businesses where 24/7 availability isn’t a priority, DDL operations can be performed during maintenance times or late at night. Even if a few users are online, at most, they might experience minor delays. However, modern internet businesses are strict about maintenance windows, creating a higher demand for non-blocking DDL, which MySQL, as a quintessential internet database, was first to support. The typical implementation involves creating a copy of the schema table, with operations being sent to both the new and old tables during the transition. ...

Background The CAP theorem has become one of the hottest theorems in recent years; when discussing distributed systems, CAP is inevitably mentioned. However, I feel that I haven’t thoroughly understood it, so I wanted to write a blog post to record my understanding. I will update the content as I gain new insights. Understanding I read the first part of this paper. The CAP theorem [Bre12] says that you can only have two of the three desirable properties of: ...

Background Travis CI is generally used for automating tests without needing to update the repository with the test outputs. This article explains how to automatically commit the results from Travis CI. Process The basic process references this gist. Below is the .travis.yml from the gist. language: ruby rvm: - 2.0.0 env: global: - USER="username" - EMAIL="[email protected]" - REPO="name of target repo" - FILES="README.md foo.txt bar.txt" - GH_REPO="github.com/${USER}/${REPO}.git" - secure: "put travis gem output here => http://docs.travis-ci.com/user/encryption-keys/" script: - ruby test.rb after_success: - MESSAGE=$(git log --format=%B -n 1 $TRAVIS_COMMIT) - git clone git://${GH_REPO} - mv -f ${FILES} ${REPO} - cd ${REPO} - git remote - git config user.email ${EMAIL} - git config user.name ${USER} - git add ${FILES} - git commit -m "${MESSAGE}" - git push "https://${GH_TOKEN}@${GH_REPO}" master > /dev/null 2>&1 Note here that MESSAGE should be quoted when committing, which the original gist did not include. ...