[BUG] sort consumes too much memory and kills itself

[jeroen-80]

🐛 Bug Description

Sorting huge (1TB+) text files crashes.

🔄 To Reproduce

Command used:

LC_ALL=C sort -u large_file*txt > all

Input data:

text1
text2
[..]

Steps to reproduce:

1. Run the command above
2. Observe stderr

✅ Expected Behavior

A sorted result file, like sort of my distro (work fine with same data).

❌ Actual Behavior

Sorting crashes with OOM:

Actual output:

an 09 02:16:54 dev kernel: Out of memory: Killed process 3526597 (sort) total-vm:1736975544kB, anon-rss:91882960kB, file-rss:0kB, shmem-rss:0kB, UID:1000 pgtables:1137628kB oom_score_adj:0

🖥️ Environment

Operating System: Debian 13
rust-sort version: sort 1.0.5
Rust version: ustc 1.92.0 (ded5c06cf 2025-12-08)
Hardware:

• CPU: Ryzen 7 7700
• RAM: 96GB
• Architecture: x86_64

📁 Additional Context

File size: 1.5TB.
Data characteristics:

• Text data
  Performance impact:
• Crash or panic