Back out "Fixing a bug where allocating a 4GB block results in using 8GB of memory (#95827)" (#96796)
Summary:
Original commit changeset: a19273017a2a
Original Phabricator Diff: D43969564
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Test Plan: unlandayc
Reviewed By: terrycsy
Differential Revision: D44080273
Pull Request resolved: https://github.com/pytorch/pytorch/pull/96796
Approved by: https://github.com/jianyuh, https://github.com/davidberard98
