Variable: undo-strong-limit

undo-strong-limit is a customizable variable defined in undo.c.

Value

240000

Documentation

Don't keep more than this much size of undo information.

This limit is applied when garbage collection happens. When a previous command increases the total undo list size past this value, that command and the earlier commands that came before it are forgotten. However, the most recent buffer-modifying command's undo info is never discarded for this reason.

The size is counted as the number of bytes occupied, which includes both saved text and other data.

This variable was added, or its default value changed, in Emacs 27.1.

View in manual

Probably introduced at or before Emacs version 19.1.

Source Code

// Defined in /usr/src/emacs/src/undo.c
  DEFVAR_INT ("undo-strong-limit", undo_strong_limit,
	      doc: /* Don't keep more than this much size of undo information.
This limit is applied when garbage collection happens.
When a previous command increases the total undo list size past this
value, that command and the earlier commands that came before it are forgotten.
However, the most recent buffer-modifying command's undo info
is never discarded for this reason.

The size is counted as the number of bytes occupied,
which includes both saved text and other data.  */);