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charset="us-ascii" Content-ID: <80D24023C6BE19499428828E95D888AB@prod.exchangelabs.com> Content-Transfer-Encoding: quoted-printable Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-OriginatorOrg: amperecomputing.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: BL1PR01MB7649.prod.exchangelabs.com X-MS-Exchange-CrossTenant-Network-Message-Id: 65b3fb70-2324-4ec1-4077-08de22481634 X-MS-Exchange-CrossTenant-originalarrivaltime: 13 Nov 2025 00:03:33.8580 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 3bc2b170-fd94-476d-b0ce-4229bdc904a7 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: ZvSWPXspPiy1WCOHvZvvBcz3Awq0aqX4jG2Or+cszwUF5jkWWXnPgF0olKOEq1YFDNbhteWqPN9l1ZKp2GGS7qMEl7NL1422YWbE56VN+zY= X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR01MB6745 Hi Vineeth, > Is cache locality prioritized even over idle CPU availability? I had assumed that the fast path prioritizes cache locality over idle CPU s= election. However, our performance measurements indicate that, in this spec= ific scenario, the trade-off is not worthwhile. The data shows that prioritizing the busy, `cache-hot` core leads to perfor= mance regressions and an overload on wakeup. Which means an overhead of st= aying on the busy core outweighs the cost of migrating to an idle core. In development, I am trying an alternative approach to benefit from cache l= ocality in this path. Regards, Shubhang Kaushik=