Remove AutoMLSearch self-reference

[freddyaboulton]

Pull Request Description

Fixes #2226

We see slightly lower memory usage at the peak (~500 mb) and the memory after the peak is lower and starts to decrease (line after peak has a negative slope as opposed to being constant).

Memory for all unit tests

Memory for automl tests

Plot still works for jupyter notebook

from evalml import AutoMLSearch
from evalml.automl.callbacks import raise_error_callback
import pandas as pd
X = pd.read_csv("/Users/freddy.boulton/Downloads/titanic_text.csv")
y = X.pop('Survived')
automl = AutoMLSearch(X, y, problem_type="binary", error_callback=raise_error_callback, max_batches=10, ensembling=True)
automl.search()

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[codecov]

Codecov Report

Merging #2304 (a92ba22) into main (961584a) will decrease coverage by 0.1%.
The diff coverage is 96.3%.

❗ Current head a92ba22 differs from pull request most recent head ade7b07. Consider uploading reports for the commit ade7b07 to get more accurate results

@@           Coverage Diff           @@
##            main   #2304     +/-   ##
=======================================
- Coverage   99.9%   99.9%   -0.0%     
=======================================
  Files        281     281             
  Lines      24606   24608      +2     
=======================================
+ Hits       24578   24579      +1     
- Misses        28      29      +1     

Impacted Files	Coverage Δ
.../automl_tests/test_automl_search_classification.py	100.0% <ø> (ø)
evalml/automl/automl_search.py	99.9% <90.0%> (-0.1%)	⬇️
evalml/automl/pipeline_search_plots.py	100.0% <100.0%> (ø)
...l/tests/automl_tests/test_pipeline_search_plots.py	100.0% <100.0%> (ø)

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[freddyaboulton]

Need this check because the api of SearchIterationPlot.update and plotly.Figure update are now different.

[angela97lin]

Got it, so this line was not covered to begin with right?

[dsherry]

@freddyaboulton thanks for sharing these plots. If I am reading them correctly, is it right to say that fixing this leak results in a slight reduction in memory consumption? I see a drop in peak memory usage on the order of ~100MB.

[freddyaboulton]

@dsherry Yes!

[freddyaboulton]

Before we kept a reference to the latest results by passing a reference to AutoMLSearch. In order to not have a self-reference but still be able to access the latest results, I'm adding results as an argument to init and update. The plot property of AutoMLSearch will always pass the latest results to the plot.

[angela97lin]

LGTM, the memory plots look great 😁

[angela97lin]

Got it, so this line was not covered to begin with right?

[chukarsten]

This looks good. Good work, nice to see some solid memory usage results.

[bchen1116]

Nice!