etseidl commented on PR #8587:
URL: https://github.com/apache/arrow-rs/pull/8587#issuecomment-3391726888

   This PR shows the value of reducing vector allocations. Two major offenders 
during decoding are the `encodings` and `page_encoding_stats` vectors in 
`ColumnChunkMetaData`. This PR gets rid of the former. The biggest impact is in 
the wide schema test.
   
   ```
   default features
   group                             encodings_default                      main
   -----                             -----------------                      
-------
   decode parquet metadata           1.00     16.2±0.28µs        ? ?/sec    
1.08     17.4±0.31µs        ? ?/sec
   decode parquet metadata (wide)    1.00     62.0±1.92ms        ? ?/sec    
1.20     74.2±1.58ms        ? ?/sec
   open(default)                     1.00     16.9±0.25µs        ? ?/sec    
1.07     18.1±0.41µs        ? ?/sec
   open(page index)                  1.01    255.8±6.08µs        ? ?/sec    
1.00    252.9±4.98µs        ? ?/sec
   
   all features
   group                             encodings_encr                         main
   -----                             --------------                         
------------
   decode parquet metadata           1.00     16.9±0.29µs        ? ?/sec    
1.07     18.0±0.32µs        ? ?/sec
   decode parquet metadata (wide)    1.00     67.6±1.37ms        ? ?/sec    
1.16     78.5±1.69ms        ? ?/sec
   open(default)                     1.00     17.5±0.35µs        ? ?/sec    
1.07     18.8±0.39µs        ? ?/sec
   open(page index)                  1.00    254.1±4.33µs        ? ?/sec    
1.00    254.6±5.31µs        ? ?/sec
   ```


-- 
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]

Reply via email to