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+performance: 0.996
+arm: 0.983
+architecture: 0.974
+x86: 0.963
+device: 0.938
+socket: 0.916
+graphic: 0.901
+user-level: 0.897
+PID: 0.895
+register: 0.886
+peripherals: 0.877
+debug: 0.861
+semantic: 0.842
+permissions: 0.841
+ppc: 0.837
+vnc: 0.817
+network: 0.817
+files: 0.779
+hypervisor: 0.766
+VMM: 0.765
+TCG: 0.747
+risc-v: 0.720
+kernel: 0.719
+KVM: 0.713
+assembly: 0.698
+i386: 0.683
+boot: 0.639
+virtual: 0.436
+mistranslation: 0.328
+
+Major qemu-aarch64 performance slowdown since commit 59b6b42cd3
+Description of problem:
+I have observed a major performance slowdown between qemu 8.0.0 and 8.1.0:
+
+
+qemu 8.0.0: 0.8s
+
+qemu 8.1.0: 6.8s
+
+
+After bisecting the commits between 8.0.0 and 8.1.0, the offending commit is 59b6b42cd3:
+
+
+commit 59b6b42cd3446862567637f3a7ab31d69c9bef51
+Author: Richard Henderson <richard.henderson@linaro.org>
+Date:   Tue Jun 6 10:19:39 2023 +0100
+
+    target/arm: Enable FEAT_LSE2 for -cpu max
+
+    Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
+    Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
+    Message-id: 20230530191438.411344-21-richard.henderson@linaro.org
+    Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
+
+
+Reverting the commit in latest master fixes the problem:
+
+qemu 8.0.0: 0.8s
+
+qemu 8.1.0: 6.8s
+
+qemu master + revert 59b6b42cd3: 0.8s
+
+Alternatively, specify `-cpu cortex-a35` to disable LSE2:
+
+`time ./qemu-aarch64 -cpu cortex-a35`: 0.8s
+
+`time ./qemu-aarch64`: 6.77s
+
+The slowdown is also observed when running qemu-aarch64 on aarch64 machine:
+
+`time ./qemu-aarch64 /usr/bin/node -e 1`: 2.91s
+
+`time ./qemu-aarch64 -cpu cortex-a35 /usr/bin/node -e 1`: 1.77s
+
+The slowdown on x86_64 machine is small: 362ms -> 378ms.
+Steps to reproduce:
+1. Run `time ./qemu-aarch64 node-aarch64 -e 1` (node-aarch64 is NodeJS v16 built for AArch64)
+2. Using qemu master, the output says `0.8s`
+3. Using qemu master with commit 59b6b42cd3 reverted, the output says `6.77s`
+Additional information:
+