[ARROW-6411] [C++][Parquet] DictEncoderImpl<T>::PutIndicesTyped has bad performance on some systems

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.15.0
• Component/s: C++
• Labels: pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/22783
• Assignee: Wes McKinney
• Reporter: Wes McKinney
• Created: 01/Sep/19 23:14
• Updated: 11/Jan/23 07:46
• Resolved: 03/Sep/19 02:40

Description

I was doing some benchmarking and noticed that this function showed up as slow due to __memmove_avx_unaligned_erms. I'm interested to investigate why this is, but for me it's fixed by changing the std::vector::reserve call to std::vector::resize and instead assigning elements into buffered_indices_. I'll add a Python benchmark that illustrates the problem to see if it shows up on other systems

Issue Links

• is related to: PARQUET-1646 [C++] Use arrow::Buffer for buffered dictionary indices in DictEncoder instead of std::vector
• links to: GitHub Pull Request #5248