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https://issues.apache.org/jira/browse/ARROW-10308?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17292214#comment-17292214
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Dror Speiser commented on ARROW-10308:
--------------------------------------

Hi Diana,

Cool!

I've created a small benchmark that spins up EC2 instances, downloads a NY Taxi 
dataset, and runs read_csv with different block sizes. I'll upload the raw data 
tomorrow, but meanwhile here is a draft basic analysis notebook on the data 
that I already have:

[https://github.com/drorspei/arrow-csv-benchmark/blob/ec2-block-size/analysis.ipynb]

If you look in the containing branch, you will find two files: a script, and a 
supporting file for boto code.

I'll be super glad to collaborate whenever I can :)

As for NUMA enabled, I think I was running Azure's E48_as_v4, which I see in 
the table on this page:

[https://docs.microsoft.com/en-us/azure/virtual-machines/linux/compute-benchmark-scores]

There's a column "NUMA Nodes" which says "6". I'm not familiar with NUMA, so I 
don't know what this means. Is there something I could run on the machine to 
check?

> [Python] read_csv from python is slow on some work loads
> --------------------------------------------------------
>
>                 Key: ARROW-10308
>                 URL: https://issues.apache.org/jira/browse/ARROW-10308
>             Project: Apache Arrow
>          Issue Type: Bug
>          Components: C++, Python
>    Affects Versions: 1.0.1
>         Environment: Machine: Azure, 48 vcpus, 384GiB ram
> OS: Ubuntu 18.04
> Dockerfile and script: attached, or here: 
> https://github.com/drorspei/arrow-csv-benchmark
>            Reporter: Dror Speiser
>            Priority: Minor
>              Labels: csv, performance
>         Attachments: Dockerfile, arrow-csv-benchmark-plot.png, 
> arrow-csv-benchmark-times.csv, benchmark-csv.py, profile1.svg, profile2.svg, 
> profile3.svg, profile4.svg
>
>
> Hi!
> I've noticed that `pyarrow.csv.read_csv` can be slow on real workloads, 
> processing data around 0.5GiB/s. "Real workloads" means many string, float, 
> and all-null columns, and large file size (5-10GiB), though the file size 
> didn't matter to much.
> Moreover, profiling a little a bit with py-spy, it seems that maybe 30-50% of 
> the time is spent on shared pointer lock mechanisms (though I'm not sure if 
> this is to be trusted). I've attached the dumps in svg format.
> I've also attached a script and a Dockerfile to run a benchmark, which 
> reproduces the speeds I see. Building the docker image and running it on a 
> large Azure machine, I get speeds around 0.3-1.0 GiB/s, and it's mostly 
> around 0.5GiB/s.
> This is all also available here: 
> https://github.com/drorspei/arrow-csv-benchmark



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