[
https://issues.apache.org/jira/browse/ARROW-14790?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17541442#comment-17541442
]
Sten Larsson commented on ARROW-14790:
--------------------------------------
I finally found some time to further investigate the, and as suggested I added
the arrow::MemoryPool::bytes_allocated function to the GLib wrapper. I created
a PR, but should I create separate Jira issue for that?
[https://github.com/apache/arrow/pull/13224]
The bytes_allocated returns zero in my original script, so I guess there is no
memory leak. However I've created another script
[arrow_memory_leak_2.rb|https://gist.github.com/stenlarsson/60b1e4e99416738b41ee30e7ba294214#file-arrow_memory_leak_2-rb]
which appear to leak when using a compute function. Here is what the output
looks like on Arrow 8.0.0 on my computer with my patch applied:
{noformat}
backend_name: mimalloc
0 MB allocated, 110459 Ruby objects
77 MB allocated, 110459 Ruby objects
154 MB allocated, 110459 Ruby objects
232 MB allocated, 110459 Ruby objects
309 MB allocated, 110459 Ruby objects
387 MB allocated, 110459 Ruby objects
464 MB allocated, 110459 Ruby objects
542 MB allocated, 110459 Ruby objects
619 MB allocated, 110459 Ruby objects
697 MB allocated, 110459 Ruby objects
774 MB allocated, 110459 Ruby objects{noformat}
> Memory leak when reading CSV files
> ----------------------------------
>
> Key: ARROW-14790
> URL: https://issues.apache.org/jira/browse/ARROW-14790
> Project: Apache Arrow
> Issue Type: Bug
> Components: C++, Python, Ruby
> Reporter: Sten Larsson
> Priority: Major
>
> We're having problem with a memory leak in a Ruby script that processes many
> CSV files. I have written some short scripts do demonstrate the problem:
> [https://gist.github.com/stenlarsson/60b1e4e99416738b41ee30e7ba294214]
> The first script,
> [arrow_test_csv.rb|https://gist.github.com/stenlarsson/60b1e4e99416738b41ee30e7ba294214#file-arrow_test_csv-rb],
> creates a 184 MB CSV file for testing.
> The second script,
> [arrow_memory_leak.rb|https://gist.github.com/stenlarsson/60b1e4e99416738b41ee30e7ba294214#file-arrow_memory_leak-rb],
> then loads the CSV file 10 times using Arrow. It uses the
> [get_process_mem|https://rubygems.org/gems/get_process_mem] gem to print the
> memory usage both before and after each iteration. It also invokes the
> garbage collector on each iteration to ensure the problem is not that Ruby
> holds on to any objects. This is what it prints on my MacBook Pro using Arrow
> 6.0.0:
> {noformat}
> 127577 objects, 34.234375 MB
> 127577 objects, 347.625 MB
> 127577 objects, 438.7890625 MB
> 127577 objects, 457.6953125 MB
> 127577 objects, 469.8046875 MB
> 127577 objects, 480.88671875 MB
> 127577 objects, 487.96484375 MB
> 127577 objects, 493.8359375 MB
> 127577 objects, 497.671875 MB
> 127577 objects, 498.55859375 MB
> 127577 objects, 501.42578125 MB
> {noformat}
> The third script, [arrow_memory_leak.py
> |https://gist.github.com/stenlarsson/60b1e4e99416738b41ee30e7ba294214#file-arrow_memory_leak-py]
> is a Python implementation of the same script. This shows that the problem
> is not in the Ruby bindings:
> {noformat}
> 2106 objects, 31.75390625 MB
> 2106 objects, 382.28515625 MB
> 2106 objects, 549.41796875 MB
> 2106 objects, 656.78125 MB
> 2106 objects, 679.6875 MB
> 2106 objects, 691.9921875 MB
> 2106 objects, 708.73828125 MB
> 2106 objects, 717.296875 MB
> 2106 objects, 724.390625 MB
> 2106 objects, 729.19921875 MB
> 2106 objects, 734.47265625 MB
> {noformat}
> I have also tested Arrow 5.0.0 and it has the same problem.
--
This message was sent by Atlassian Jira
(v8.20.7#820007)
