After merging your PR, Conbench analyzed the 6 benchmarking runs that have been run so far on merge-commit be1b003.

Benchmarks with performance regressions

There were 2 possible performance regressions, according to the lookback z-score method.

Benchmarks with regressions:

• Commit Run on ursa-i9-9960x at 2023-08-13 23:40:22Z
  • tpch (R) with engine=arrow, format=parquet, language=R, memory_map=False, query_id=TPCH-06, scale_factor=1
  • tpch (R) with engine=arrow, format=native, language=R, memory_map=False, query_id=TPCH-06, scale_factor=1

All benchmark runs analyzed:

• Commit Run on ec2-t3-xlarge-us-east-2 at 2023-08-10 20:14:10Z
• Commit Run on arm64-t4g-linux-compute at 2023-08-10 22:17:09Z
• Commit Run on ec2-m5-4xlarge-us-east-2 at 2023-08-10 22:21:42Z
• Commit Run on arm64-m6g-linux-compute at 2023-08-11 05:36:42Z
• Commit Run on ursa-thinkcentre-m75q at 2023-08-12 06:59:17Z
• Commit Run on ursa-i9-9960x at 2023-08-13 23:40:22Z

Unstable benchmarks with performance regressions

The following benchmark results indicate a possible performance regression, but are known to sometimes produce false positives when applying the lookback z-score analysis.

• Commit Run on arm64-t4g-linux-compute at 2023-08-10 22:17:09Z

  • BM_PlainEncodingSpacedBoolean (C++) with params=32768/1, source=cpp-micro, suite=parquet-encoding-benchmark
  • BM_PlainEncodingSpacedBoolean (C++) with params=32768/100, source=cpp-micro, suite=parquet-encoding-benchmark
  • BM_PlainEncodingSpacedBoolean (C++) with params=32768/1000, source=cpp-micro, suite=parquet-encoding-benchmark
  • ErrorSchemeBoolNoInline (C++) with source=cpp-micro, suite=arrow-type-benchmark

• Commit Run on arm64-m6g-linux-compute at 2023-08-11 05:36:42Z

  • BM_PlainEncodingBoolean (C++) with params=1024, source=cpp-micro, suite=parquet-encoding-benchmark
  • BM_WriteColumn (C++) with params=<false,BooleanType>, source=cpp-micro, suite=parquet-arrow-reader-writer-benchmark
  • BM_PlainEncodingBoolean (C++) with params=4096, source=cpp-micro, suite=parquet-encoding-benchmark
  • BM_PlainEncodingSpacedBoolean (C++) with params=32768/100, source=cpp-micro, suite=parquet-encoding-benchmark
  • BM_PlainEncodingSpacedBoolean (C++) with params=32768/1000, source=cpp-micro, suite=parquet-encoding-benchmark
  • BM_PlainEncodingSpacedBoolean (C++) with params=32768/1, source=cpp-micro, suite=parquet-encoding-benchmark

• Commit Run on ursa-thinkcentre-m75q at 2023-08-12 06:59:17Z

  • BM_PlainEncodingSpacedBoolean (C++) with params=32768/5000, source=cpp-micro, suite=parquet-encoding-benchmark
  • BM_DeltaBitPackingEncode_Int32_Narrow (C++) with params=32768, source=cpp-micro, suite=parquet-encoding-benchmark
  • BM_DictDecodingInt64_repeats (C++) with params=32768, source=cpp-micro, suite=parquet-encoding-benchmark
  • BM_DictDecodingInt64_repeats (C++) with params=4096, source=cpp-micro, suite=parquet-encoding-benchmark
  • BM_DictDecodingInt64_repeats (C++) with params=65536, source=cpp-micro, suite=parquet-encoding-benchmark
  • BM_PlainEncodingSpacedBoolean (C++) with params=32768/1, source=cpp-micro, suite=parquet-encoding-benchmark
  • ValidateSmallAscii (C++) with source=cpp-micro, suite=arrow-utf8-util-benchmark
  • BM_PlainEncodingSpacedBoolean (C++) with params=32768/100, source=cpp-micro, suite=parquet-encoding-benchmark
  • BM_PlainEncodingSpacedBoolean (C++) with params=32768/1000, source=cpp-micro, suite=parquet-encoding-benchmark