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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?8EROcBPv/oD2XbgEi9uSbPSNmeQAbCLQ8jJbQB6Zuoh5KaLn7N/CUPOhgx4Y?= =?us-ascii?Q?OrcpJ9sSu6o9uQgZf+iXAvnL/BtQq1Z3QwO77Xs/idX5JkeUSH9PhoyfFBVV?= =?us-ascii?Q?LNb7I997rQzDSy5ZGRw8FQBE/LBSbYC7wvZ9F8emI1pHVVTZBot87fG1NY4u?= =?us-ascii?Q?ZdMUvbPywpZuYJ5+90cZ4cBYrZNstw59XLyujl57R73kwsntTHJDxG275UW3?= =?us-ascii?Q?ifrMmqVRwMvQeRZqS/5GMcbJ2IkD4fPQahIxErB8vOCR/sT3Nl2HFAPnWSHy?= =?us-ascii?Q?9jpNTyttG5t8EUD+2ymfE4o+CIV1dQY12GqMk+JPU2yPmAhH9tY8dzqZbGz1?= =?us-ascii?Q?gaz6XRl1rWiMBHOdRGLoCEBhf6FNS1JNErnj2IIYEIzDpyyNgejC6zuH9vLH?= =?us-ascii?Q?wWblDLXdNOBa0HNlAEJKj9KT3RPekMo1LY782aau0l8cD3npnu2S8tTSSHkR?= =?us-ascii?Q?hwO6kSzPCDz5B+UIQ6cmHe/LFArJ/LfF2Is8ggwnDepTKrktKMCsewjP/R63?= =?us-ascii?Q?4kboAimrqn6vtg4F9m4GCEEjWth9pi8jPEXOPAPbgVKesXRQUKnCF+tKtN5S?= =?us-ascii?Q?c5R9OzfYAwLOLfYPHZMC6ELWDkFPGejHiN8laI553u3fmSicFtvzShnVk6B3?= =?us-ascii?Q?joMlDGcPdYmxFWhjHsByw0f+KjPq5Ipjqp7p07OfniQv6F8F6IXLquOZEqZm?= =?us-ascii?Q?nSE4QG0RTmEHpyxK3jIPUBKmCeAaRwsbKzA/zGfjH9fgmNoCiQxjpz5EUOsW?= =?us-ascii?Q?E+7j3nZ1UvHAe8P5a3XT3OCTT5+JIWv1Qn8D2ayOcXXnxUaPLU1aaWEkKpIn?= =?us-ascii?Q?PoYVn85rflx0PtZi9HRfQ9jboGmrr4H7/+i7O00oMSO/ySy2Dsp5pp86dxY5?= =?us-ascii?Q?MDEzwDPRgs1TmEN/UjK/b2+QJ3qWtHt6vGbhvS5L8YT4uzlGF0p1h0UDjC07?= =?us-ascii?Q?O45EykpT/4y8wSEoaD5RLeAd4+buiOV4gc2iKpc0iD1vPTAZoq8hs9pC2fdD?= =?us-ascii?Q?VJisfUixctUN2d0wdNg8tgV9btCcUJs2MRkIF2fc5oqY8dBgW3/bY8BqTET1?= =?us-ascii?Q?HW61sWg1+GqZ84/Flfir3CsJYkkDDNP+8nxX2kikcuxJqwhvC/yXsZJawG78?= =?us-ascii?Q?bKizCGC/j06OP4FpaBwNuoSC9WRfpayMca9EfCyALmp7tscpNS9PWSWTFSsQ?= =?us-ascii?Q?EJilBJtG1pEfgQxE4a8hH1N6feo4tLaCY9jAj7BRU4qVB1+WtfODeByGKfmA?= =?us-ascii?Q?mBB5mNUIbpJwDiGrMdmBJAHRKalYAvTqssEHbdab063eGaG/OhWHXZZ5LT65?= =?us-ascii?Q?Q+838BzeHUKnIkyprWZG/VVx4u/KxfdYoHjfBOrtVk+r2RxFGVtzm5ZGwYFL?= =?us-ascii?Q?bgUpTVzb0Q1w4XB0kXzN0GTe13V1s4Nw/E63nruPASE0CxbelP2e9H3EP/D6?= =?us-ascii?Q?LEIsyQHtix2rOs17h3ufYaOQhbFWC8heG3ORwoVXD1zs7UiuLiOnfIAaEJtK?= =?us-ascii?Q?qjiCi6pQjEkU7bGJCbihrk1olgG24ALszlxPjvgXA/hXXDh0yGN6VtPJfImm?= =?us-ascii?Q?nszUN3bmoksAanQ7TlxhfaPpgS4EiikwkO5TjZlh?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: c61b7687-ea7f-4bf9-421b-08dd53deb818 X-MS-Exchange-CrossTenant-AuthSource: CY5PR12MB6405.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 23 Feb 2025 07:50:19.4708 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: f7VPlcOchzl1cU+HcF34IA89zDS9ZjyCxp9kEfW7XbKTEohjopCS501bBGr6dO8Mlv06gfzqRWql+Tisc6l+KQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA3PR12MB9091 On Wed, Feb 12, 2025 at 09:50:54AM -0500, Joel Fernandes wrote: > On Mon, Feb 10, 2025 at 12:19:15AM +0000, Qais Yousef wrote: ... > > I believe HZ_250 was the default as a trade-off for battery power > > devices that might not be happy with frequent TICKS potentially draining > > the battery unnecessarily. But to my understanding the current state of > > Actually, on x86, me and Steve did some debug on Chromebooks and we found > that HZ_250 actually increased power versus higher HZ. This was because > cpuidle governor changes C states on the tick, and by making it less > frequent, the CPU could be in a shallow C state for longer. FWIW, I found the same about power consumption when we decided to switch to CONFIG_HZ=1000 in the Ubuntu kernel: https://discourse.ubuntu.com/t/enable-low-latency-features-in-the-generic-ubuntu-kernel-for-24-04/42255 -Andrea