renyd123 commented on issue #42097: URL: https://github.com/apache/arrow/issues/42097#issuecomment-2161096430
> I've check the code here: > > https://github.com/apache/arrow/blob/03a960de86d0c3ce8bf299724c94be5b291d85b4/cpp/src/parquet/arrow/reader.cc#L1247-L1284 > > CPU Executor is used when enabled ( C++ disable use_thread by default ), and per-thread calls a to emit the column out, generally it couldn't get slower here. I guess maybe that's because contention on CPU thread or other reason 🤔, maybe I can draft some benchmark later this week`use_thread``ReadColumn` I deliberately turned off 'use_thread' and instead manually called 'reader->RowGroup(i)->ReadTable(&table)' with multiple threads just like: ` threads.push_back(std::thread([&reader, i]() { reader->RowGroup(i)->ReadTable(&table); }));` -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
