v2.0.0

Summary

Backup-request

• feat: implement backup request (#93)
• refactor(rpc): refactor request meta to adapt to new version of rpc protocol (#82)

Requirement: Pegasus server >= 2.0.0

Backup-request allows users to read from the secondary replica when latency from primary exceeds a preconfigured threshold.
It could help reduce the tail latency (p999 or higher) and achieve more stable performance.

Related discussion:

• apache/incubator-pegasus#251
• #84

Docs: http://pegasus.apache.org/administration/backup-request

Scan-limit

• feat: handle scan iteration exceed limit and refactor code (#96)

Requirement: Pegasus server >= 1.12.3

Other new features

• feat: forbid large-size-value written to pegasus server (#95)
• feat: add configuration for meta query timeout (#103)
• improvement: add detailed information when operation has exception (#106)

Bugfix

• Release streams resource while loading config (#113)
• fix: startSortKey can't pass null (#108)
• fix: use origin expireNanoTime to init new clientRequestRound (#105)
• fix: make SetItem Serializable (#101)
  This fix resolves the problem that writing to Pegasus in Spark will raise an exception since SetItem is unserializable.

Misc

• refactor: optimize perf-counter (#98)
• refactor: delete unused log in TableHandler (#87)
• refactor: reduce parameters in construction of internal Table and Cluster (#104)
• build: add maven-shade for thrift (#71)

Compatibility Note

v2.0.0 is only for >= Pegasus 2.0, otherwise, it will have compatibility problem which throw ERR_SESSION_RESET exception