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X-OriginatorOrg: arm.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 16 Jan 2023 16:34:09.0318 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 52a0c270-7073-426b-1da6-08daf7df7e10 X-MS-Exchange-CrossTenant-Id: f34e5979-57d9-4aaa-ad4d-b122a662184d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=f34e5979-57d9-4aaa-ad4d-b122a662184d;Ip=[63.35.35.123];Helo=[64aa7808-outbound-1.mta.getcheckrecipient.com] X-MS-Exchange-CrossTenant-AuthSource: AM7EUR03FT062.eop-EUR03.prod.protection.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: PAWPR08MB9567 X-Spam-Status: No, score=-5.0 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,FORGED_SPF_HELO,KAM_DMARC_NONE,RCVD_IN_DNSWL_NONE,RCVD_IN_MSPIKE_H2,SPF_HELO_PASS,SPF_NONE,TXREP,UNPARSEABLE_RELAY autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: Hi Noah,=0A= =0A= > If it's a long running benchmark (increased iteration count) then the=0A= > OS preemption=0A= > effect should scale up and the constant cost of the 2x function calls=0A= > / going to the=0A= > OS for getting the time should scale down proportionally.=0A= >=0A= > Maybe we just need two timer apis for `TIMING_NOW_LONG` and=0A= > `TIMING_NOW_SHORT`?=0A= =0A= Many benchtests run a fixed number of iterations on varying inputs (eg.=0A= string of size 1 vs 10000), so you wouldn't statically know which timer to = use. =0A= Targets that have timer overflow issues (eg. Alpha) don't use it at all in = the=0A= benchtests.=0A= =0A= Cheers,=0A= Wilco=0A=