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charset=us-ascii Content-Disposition: inline In-Reply-To: <20260522195426.6e764847f4c4dcbaad388291@linux-foundation.org> X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 3AD8DC0004 X-Rspam-User: X-Stat-Signature: ux7y5tfqkcebc6c6h5ixuyca3zn7whtb X-HE-Tag: 1779544248-44474 X-HE-Meta: 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 E6BSbLu0 gQZLm0v5x0NM+Dlu2Q5tXu6mHgajGfT++qJG3HIEiUv2uirYV2TMcvC23xqApDqZU416UwOm+Dq2CMnSy1YvL+jqYlGWFaDNECBhZsSRRVDf2bD7/KeLG1zxe4BmvO1zHx+v5hrcA6eK7noK2q7YOXUcAGDLt95UhtdLpezKuHokhoT1aoXYR16IryOlbebvPq9DBr4m6kWkXYMg4/KJnwinsS23f3xsajY1M2boDfTYSOthHj+VhdFE77UbjDyluljctvV1ulEqxBLymmGVW0szfgEV3ABbx9nQc2nFy+pKr4mxtijhMrKBJaadEhsHl3OB0NSmcFxRTaElDB/xhK8N92Q== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, May 22, 2026 at 07:54:26PM -0700, Andrew Morton wrote: > On Fri, 22 May 2026 13:05:36 +0000 Dmitry Ilvokhin wrote: > > > > How serious is this to our users when running real-world workloads? > > > > We observed it on a few of the Meta workloads that adopted > > defrag_mode=1. > > > > For the service under load there were 85509 SLUB allocation failures > > messages in dmesg within 2 hours. All of them are GFP_ATOMIC allocations > > for skbuff_head_cache, despite free pages being available in other > > migratetype freelists (~13 GB free). > > For a single machine, I assume. Yes, all of that data is from a single machine. > > > Since it is networking path from the practical point of view, this means > > dropped packets, failed RPC requests, tail latency spikes and overall > > service degradation. > > OK, thanks. I assume 12 failures per second isn't a disaster, and that > there's no need to fast-track this into 7.1? Yes, I agree. No need to fast-track this.