Weekly update (August 05 ~ August 12, 2016)

Last week, we landed 20 PRs in the TiDB repositories and 11 PRs in the TiKV repositories.

Notable changes to TiDB

• Rewrite Lexer and improve the speed of parsing SQL texts by 40%.
• Add a command line flag for log output file and rotate log files regularly.
• Optimize the 2 phase commit process and adopt faster methods to clear locks.
• Optimize the execution speed of the Insert On Duplicate Update statement.
• Update the Documents repository.
• Fix several bugs.

Notable changes to TiKV

• Support the Scan and Resolve transaction lock.
• Support garbage collection(GC) stale peer.
• Use a Write column family to store transaction commit logs.
• Remove the unnecessary Seek operation.
• Fix random quorum test.

Notable changes to Placement Driver

• Support the get PD leader API.