[Python] Altair fails when making faceted histogram with large dataset

When I try to make histogram with Altair with the code (n=1million) below,

import polars as pl
import numpy as np
import altair as alt

n = 1000000
s = np.random.normal(0, 1, n)
h = np.random.normal(0, 1, n)
df = pl.DataFrame({"value": s, "h": h}).with_columns(
pl.when(pl.col("h") > 0)
.then(pl.lit("high"))
.otherwise(pl.lit("low"))
.alias("high_low"),
pl.lit(0.5).alias("a"),
)

chart1 = (
alt.Chart().mark_bar().encode(alt.X("value").bin(), y=alt.Y("count()", title="Pcs"))
)

chart2 = alt.Chart().mark_rule().encode(x="a")

chart = (chart1 + chart2).facet(row="high_low", data=df)

chart.save("./Python/trial/altair_histogram_trial16.png")


Error below comes out and chart is not saved.

<--- Last few GCs --->
28[30152:000001797F667000] 14256 ms: Mark-Compact (reduce) 1399.8 (1400.9) -> 1399.0 (1401.1) MB, pooled: 0 MB, 546.81 / 0.00 ms (+ 0.4 ms in 0 steps since start of marking, biggest step 0.0 ms, walltime since start of marking 550 ms) (average mu = 0.23[30152:000001797F667000] 15447 ms: Mark-Compact (reduce) 1400.0 (1401.1) -> 1399.2 (1401.4) MB, pooled: 0 MB, 1067.80 / 0.00 ms (+ 0.1 ms in 0 steps since start of marking, biggest step 0.0 ms, walltime since start of marking 1071 ms) (average mu = 0.

<--- JS stacktrace --->



#
# Fatal JavaScript out of memory: Reached heap limit
#
==== C stack trace ===============================

CrashForExceptionInNonABICompliantCodeRange [0x00007FF87E1E184B+1316923]
wgpu_render_bundle_draw_indexed_indirect [0x00007FF87DECE157+1048900]
wgpu_render_bundle_draw_indexed_indirect [0x00007FF87DF29D7A+1424743]
wgpu_render_bundle_draw_indexed_indirect [0x00007FF87DEAB84C+907321]
wgpu_render_bundle_draw_indexed_indirect [0x00007FF87DFB5EE7+1998548]
wgpu_render_bundle_draw_indexed_indirect [0x00007FF87DFB3D30+1989917]
CrashForExceptionInNonABICompliantCodeRange [0x00007FF87E3E68D7+3434695]
CrashForExceptionInNonABICompliantCodeRange [0x00007FF87E3E7756+3438406]
wgpu_render_bundle_draw_indexed_indirect [0x00007FF87DFDAC6D+2149466]
CrashForExceptionInNonABICompliantCodeRange [0x00007FF87E93C6DD+9029325]
CrashForExceptionInNonABICompliantCodeRange [0x00007FF87F2FC13A+19251498]
(No symbol) [0x00007FF7FF5CB179]



On the other hand, with smaller dataset (n=1K) below, I can make histogram. How can I make it with large dataset(1million)?

OS: Windows11 Python: version 3.13.1 RAM: 64GB Altair: version 1.20.0

import polars as pl
import numpy as np
import altair as alt

n = 1000
s = np.random.normal(0, 1, n)
h = np.random.normal(0, 1, n)
df = pl.DataFrame({"value": s, "h": h}).with_columns(
pl.when(pl.col("h") > 0)
.then(pl.lit("high"))
.otherwise(pl.lit("low"))
.alias("high_low"),
pl.lit(0.5).alias("a"),
)

chart1 = (
alt.Chart().mark_bar().encode(alt.X("value").bin(), y=alt.Y("count()", title="Pcs"))
)

chart2 = alt.Chart().mark_rule().encode(x="a")

chart = (chart1 + chart2).facet(row="high_low", data=df)

chart.save("./Python/trial/altair_histogram_trial17.png")





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