[
https://issues.apache.org/jira/browse/ARROW-7059?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Eric Kisslinger updated ARROW-7059:
-----------------------------------
Attachment: image-2019-11-06-08-23-18-897.png
> [Python] Reading parquet file with many columns is much slower in 0.15.x
> versus 0.14.x
> --------------------------------------------------------------------------------------
>
> Key: ARROW-7059
> URL: https://issues.apache.org/jira/browse/ARROW-7059
> Project: Apache Arrow
> Issue Type: Bug
> Components: Python
> Affects Versions: 0.15.1
> Environment: Linux OS with RHEL 7.7 distribution
> blkcqas037:~$ lscpu
> Architecture: x86_64
> CPU op-mode(s): 32-bit, 64-bit
> Byte Order: Little Endian
> CPU(s): 32
> On-line CPU(s) list: 0-31
> Thread(s) per core: 2
> Core(s) per socket: 8
> Socket(s): 2
> NUMA node(s): 2
> Vendor ID: GenuineIntel
> CPU family: 6
> Model: 79
> Model name: Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz
> Reporter: Eric Kisslinger
> Priority: Major
> Labels: performance
> Attachments: image-2019-11-06-08-18-42-783.png,
> image-2019-11-06-08-19-11-662.png, image-2019-11-06-08-23-18-897.png
>
>
> Reading Parquet files with large number of columns still seems to be very
> slow in 0.15.1 compared to 0.14.1. I using the same test used in
> https://issues.apache.org/jira/browse/ARROW-6876 except I set
> {{use_threads=False}} to make for an apples-to-apples comparison with respect
> to # of CPUs.
> {{import numpy as np}}
> {{import pyarrow as pa}}
> {{import pyarrow.parquet as pq}}
> {{table = pa.table(\{'c' + str(i): np.random.randn(10) for i in
> range(10000)})}}
> {{pq.write_table(table, "test_wide.parquet")}}
> {{res = pq.read_table("test_wide.parquet")}}
> {{print(pa.__version__)}}
> use_threads=False
> {{%time res = pq.read_table("test_wide.parquet", use_threads=False)}}
> *In 0.14.1 with use_threads=False:*
> {{0.14.1}}
> {{CPU times: user 515 ms, sys: 9.3 ms, total: 524 ms}}
> {{Wall time: 525 ms}}
> **
> *In 0.15.1 with* *use_threads=False**:*
> {{0.15.1}}
> {{CPU times: user 9.89 s, sys: 37.8 ms, total: 9.93 s}}
> {{Wall time: 9.93 s}}
> {{}}
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
