Potential fix for peformance regression in #14415

[etseidl]

Description

Potentially fixes #14415

Checklist

• I am familiar with the Contributing Guidelines.
• New or existing tests cover these changes.
• The documentation is up to date with these changes.

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[vuule]

/ok to test

[etseidl]

I'm hoping some enterprising soul can run the V100 benchmark as @GregoryKimball did here, as I lack access to a machine with that card. The resultant PTX code from this patch appears similar to the code with the lines commented out as was done here.

Edit: I scrounged up an AWS instance with a V100.
Current 24.02

## parquet_read_io_compression

### [0] Tesla V100-SXM2-16GB

|    io_type    | compression_type | cardinality | run_length | Samples | CPU Time | Noise | GPU Time | Noise | bytes_per_second | peak_memory_usage | encoded_file_size |
|---------------|------------------|-------------|------------|---------|----------|-------|----------|-------|------------------|-------------------|-------------------|
| DEVICE_BUFFER |             NONE |        1000 |          1 |      1x |  1.568 s |  inf% |  1.568 s |  inf% |        342429271 |       673.217 MiB |       162.287 MiB |

This PR:

## parquet_read_io_compression

### [0] Tesla V100-SXM2-16GB

|    io_type    | compression_type | cardinality | run_length | Samples | CPU Time | Noise | GPU Time | Noise | bytes_per_second | peak_memory_usage | encoded_file_size |
|---------------|------------------|-------------|------------|---------|----------|-------|----------|-------|------------------|-------------------|-------------------|
| DEVICE_BUFFER |             NONE |        1000 |          1 |      1x |  1.391 s |  inf% |  1.391 s |  inf% |        386060375 |       673.217 MiB |       162.287 MiB |

[etseidl]

Ran a few more benchmarks.

# parquet_read_io_compression

## [0] Tesla V100-SXM2-16GB

|  io_type  |  compression_type  |  cardinality  |  run_length  |   Ref Time |   Ref Noise |   Cmp Time |   Cmp Noise |           Diff |   %Diff |
|-----------|--------------------|---------------|--------------|------------|-------------|------------|-------------|----------------|---------|
| FILEPATH  |        NONE        |       0       |      1       |    1.625 s |       0.66% |    1.470 s |       0.56% | -154711.073 us |  -9.52% |
| FILEPATH  |        NONE        |     1000      |      1       |    1.596 s |       0.68% |    1.431 s |       0.34% | -165286.755 us | -10.36% |
| FILEPATH  |        NONE        |       0       |      32      |    1.335 s |       1.03% |    1.227 s |       0.35% | -108180.764 us |  -8.10% |
| FILEPATH  |        NONE        |     1000      |      32      |    1.325 s |       1.42% |    1.218 s |       0.38% | -106670.858 us |  -8.05% |

# Summary

- Total Matches: 4
  - Pass    (diff <= min_noise): 0
  - Unknown (infinite noise):    0
  - Failure (diff > min_noise):  4

# parquet_read_misc_options

## [0] Tesla V100-SXM2-16GB

|  column_selection  |  row_selection  |  str_to_categories  |  uses_pandas_metadata  |  timestamp_type  |   Ref Time |   Ref Noise |   Cmp Time |   Cmp Noise |           Diff |   %Diff |
|--------------------|-----------------|---------------------|------------------------|------------------|------------|-------------|------------|-------------|----------------|---------|
|        ALL         |       ALL       |         YES         |          YES           |      EMPTY       |    1.851 s |       0.37% |    1.738 s |       0.16% | -113446.582 us |  -6.13% |
|        ALL         |       ALL       |         YES         |           NO           |      EMPTY       |    1.849 s |       0.79% |    1.736 s |       0.27% | -112959.448 us |  -6.11% |
|        ALL         |       ALL       |         NO          |          YES           |      EMPTY       |    1.857 s |       0.64% |    1.744 s |       0.38% | -112959.587 us |  -6.08% |
|        ALL         |       ALL       |         NO          |           NO           |      EMPTY       |    1.857 s |       0.78% |    1.747 s |       0.40% | -109776.286 us |  -5.91% |

# Summary

- Total Matches: 4
  - Pass    (diff <= min_noise): 0
  - Unknown (infinite noise):    0
  - Failure (diff > min_noise):  4

# parquet_read_decode

## [0] Tesla V100-SXM2-16GB

|  data_type  |    io_type    |  cardinality  |  run_length  |   Ref Time |   Ref Noise |   Cmp Time |   Cmp Noise |          Diff |   %Diff |
|-------------|---------------|---------------|--------------|------------|-------------|------------|-------------|---------------|---------|
|    LIST     | DEVICE_BUFFER |       0       |      1       | 110.952 ms |       0.40% | 100.717 ms |       0.36% | -10235.271 us |  -9.22% |
|    LIST     | DEVICE_BUFFER |     1000      |      1       | 100.905 ms |       1.66% |  92.029 ms |       1.43% |  -8875.930 us |  -8.80% |
|    LIST     | DEVICE_BUFFER |       0       |      32      |  85.347 ms |       1.55% |  78.988 ms |       1.64% |  -6359.139 us |  -7.45% |
|    LIST     | DEVICE_BUFFER |     1000      |      32      |  86.960 ms |       1.44% |  81.678 ms |       1.95% |  -5281.288 us |  -6.07% |

# Summary

- Total Matches: 4
  - Pass    (diff <= min_noise): 0
  - Unknown (infinite noise):    0
  - Failure (diff > min_noise):  4

[GregoryKimball]

Wow @etseidl it looks like you solved the mystery!!

[etseidl]

Wow @etseidl it looks like you solved the mystery!!

Nah, you solved the mystery @GregoryKimball, I just submitted the PR 😅

[vuule]

/ok to test

[vuule]

Looks like this is the only spot where I got "creative" with the control flow. Looks good now.
Thank you for solving this!

[davidwendt]

/merge