https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109812
--- Comment #23 from Hongtao Liu <liuhongt at gcc dot gnu.org> --- (In reply to edison from comment #22) > for 607.cactuBSSN_s,if use preENV_GOMP_CPU_AFFINITY = 0-23 in CPU2017 .cfg, > all p-core(i9-13900k) usage will down to 15%(the e-core almost 100%), if > comment out it all p-core usage will up to 60%. > > 607.cactuBSSN_s on i9-13900K > gcc 14.1 > > preENV_GOMP_CPU_AFFINITY = 0-23： 60.1 (-41.7 % slower) > # preENV_GOMP_CPU_AFFINITY = 0-23： 103 > > but for AMD Zen4(+) that maybe another story so far(AMD Zen4 need > preENV_GOMP_CPU_AFFINITY to make the threads run on high performance core > first). Because E-core run slower than P-core, if you bind the thread to each core, it prevents threads from migrating from the E-core to the P-core.
