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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.56.2 (3.56.2-2.fc42) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Sun, 2026-02-01 at 16:50 -0800, Usama Arif wrote: >=20 > 1. Static Reservation: hugetlbfs requires pre-allocating huge pages > at boot > =C2=A0=C2=A0 or runtime, taking memory away. This requires capacity plann= ing, > =C2=A0=C2=A0 administrative overhead, and makes workload orchastration mu= ch > much more > =C2=A0=C2=A0 complex, especially colocating with workloads that don't use > hugetlbfs. >=20 To address the obvious objection "but how could we possibly allocate 1GB huge pages while the workload is running?", I am planning to pick up the CMA balancing=C2=A0 patch series (thank you, Frank) and get that in an=C2=A0 upstream ready shape soon. https://lkml.org/2025/9/15/1735 That patch set looks like another case where no amount of internal testing will find every single corner case, and we'll probably just want to merge it upstream, deploy it experimentally, and aggressively deal with anything that might pop up. With CMA balancing, it would be possibly to just have half (or even more) of system memory for movable allocations only, which would make it possible to allocate 1GB huge pages dynamically. --=20 All Rights Reversed.