Hi, Now, I meet some performance problem when test 4 cores SMP benchmark of seL4bench on our platform. Out platform is XXX, But I get the test data of IMX8MM_EVK_64 and TX2 platform from seL4 website, I think they are official statistics. My test results below: ARM platform Test item XXX IMX8MM_EVK_64 TX2 mean(Stddev) 500 cycles, 1 core 636545(46) 625605(29) 598142(365) 500 cycles, 2 cores 897900(2327) 1154209(44) 994298(94) 500 cycles, 3 cores 1301679(2036) 1726043(65) 1497740(127) 500 cycles, 4 cores 1387678(549) 2172109(12674) 1545872(109) 1000 cycles, 1 core 636529(42) 625599(22) 597627(161) 1000 cycles, 2 cores 899212(3384) 1134110(34) 994437(541) 1000 cycles, 3 cores 1297322(5028) 1695385(45) 1497547(714) 1000 cycles, 4 cores 1387149(456) 2174605(81) 1545716(614) From these compare data: 1. When test smp bench on one core, the performance of several platform is similar 2. When test smp bench on muti core, the result of IMX8MM_EVK_64 is beauty, the result of 4 cores is 3.47 times as good as 1 core, I think it’s good 3. But the platform of TX2 has some different performance, the result of 2 cores is 1.66 times as good as 1 core, I still think is good, But the result of 3 cores almost have the same ping-pong count with 4 cores, why add one core, the count result not add as our expected ? 4. The performance of our platform is badly, on our platform, the result of 3 cores almost also have the same ping-pong count with 4 cores, and our count result of 4 cores just 2 times as good as one core, I think it is very bad 5. I want to know what are the possible causes of the badly performance about our platform XXX and TX2 ?