Weekly update in TiDB

Last week, we landed 26 PRs in the TiDB repositories.

Added

• Update etcd client in vendor.

• Add builtin function time-to-sec

• Add definition for builtin functions: bit_count , to_base64 , right

Fixed

• Fix the error message for data overflow.

• Fix a panic.

• Fix a bug in top-n pushdown.

• Fix a data race bug in session context.

• Fix a bug in name resolver for GroupBy clause.

Improved

• Refactor optimizer: Implement new planner interface for projection and sort.

• Refactor statistic module.#3014, #3019, #3029, #3031, #3044, #3048, #3053

• Refactor coprocessor architecture: #3009, #3027

• Use etcd for privilege update notification among tidb-servers.

• Enlarge the limitation of write flow to TiKV.

• Reduce memory usage in HashAggregate operator.

• Reduce memory usage in Distinct operator.

• Code cleanup in type infer.

New Contributors

Thank you guys!

• Xuanwo

• fudali113

Weekly update in TiKV

Last week, We landed 18 PRs in the TiKV repositories.

Added

• Support memory profiling.

• Add block cache monitoring.

• Add log for critical operations.

• Use tokio-core to support asynchronous PD client, see 1745, 1752, 1753.

Fixed

• Always update PD client to avoid the problem that PD client can not reconnect to PD server after network error.

• Fix the bug when decode empty data to a StringSlice.

• Fix a deadlock bug when PD client reconnects server.

Improved

• Add lots of test cases to improve stability, see 1737 , 1738, 1742.