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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Runaway memory use when repeatedly printing empty string","articleBody":"# Bug report\n\n### Bug description:\n\nPrinting the empty string in a loop seems to cause memory use of Python to grow without bound.\n\n```python\nwhile True:\n    print('', end='')\n```\nor\n```python\nimport sys\n\nwhile True:\n    sys.stdout.write('')\n```\nThe latter apparently does not work in interactive mode.\n\nRelatedly,\n```python\nwhile True:\n    for _ in range(10**8):\n        print('', end='')\n    print()\n```\ncauses memory use to grow to about 1.5GB and then reset when the newline is printed.\n\n### CPython versions tested on:\n\n3.14, 3.11, 3.13\n\n### Operating systems tested on:\n\nLinux\n\n\u003c!-- gh-linked-prs --\u003e\n### Linked PRs\n* gh-151817\n* gh-152071\n* gh-152072\n* gh-152073\n* gh-152244\n\u003c!-- /gh-linked-prs --\u003e\n","author":{"url":"https://github.com/pastries-yay","@type":"Person","name":"pastries-yay"},"datePublished":"2026-06-20T18:29:45.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":5},"url":"https://github.com/151814/cpython/issues/151814"}