all Python 3Exceptionsexception

MemoryError

built-in exceptions

Raised when an operation runs out of memory — for example, when building a huge list.

Syntax

raise MemoryError

It rarely means the machine is out of RAM — usually one greedy operation is to blame: a billion-element list, giant string concatenation, reading a huge file in one gulp. The fix is generators and streaming, not an except block. Don't count on catching it either: on Linux with overcommit the kernel tends to kill the process via the OOM killer before Python ever raises anything.

Examples

try:
    raise MemoryError
except MemoryError as e:
    print(type(e).__name__)   # → MemoryError

See also

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