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+performance: 0.801
+graphic: 0.774
+KVM: 0.731
+architecture: 0.704
+x86: 0.571
+device: 0.568
+hypervisor: 0.479
+network: 0.455
+files: 0.434
+PID: 0.394
+kernel: 0.372
+vnc: 0.328
+semantic: 0.319
+ppc: 0.316
+socket: 0.287
+permissions: 0.272
+user-level: 0.266
+debug: 0.249
+boot: 0.237
+virtual: 0.227
+risc-v: 0.215
+VMM: 0.201
+register: 0.200
+TCG: 0.194
+peripherals: 0.142
+arm: 0.131
+i386: 0.119
+mistranslation: 0.088
+assembly: 0.068
+
+Emulated newer x86 chipsets are noticably slower on cpu-bound loads than "-cpu qemu64"
+Description of problem:
+I noticed that "-cpu qemu64" is much faster than "-cpu max" or "-cpu Icelake-Server-noTSX" for cpu bound loads, and with more than one cpu under load.
+Steps to reproduce:
+1. Run a guest as per "qemu-system-x86_64 -cpu max [..]" command from above. Any linux distro should do.
+2. run through the setup questions if you use Fedora-Server-KVM-41-1.4.x86_64.qcow2 from the example command line above
+3. log into the guest via ssh, i.e. "ssh chris@amd64" here
+4. cd /dev/shm; wget http://archive.apache.org/dist/httpd/httpd-2.4.57.tar.bz2; wget https://fluxcoil.net/files/tmp/job_httpd_extract_cpu.sh
+6. bash ./job_httpd_extract_cpu.sh 4 300
+8. cat /tmp/counter
+
+Step 6 is executing a script which simply uses 4 parallel loops, where each loop runs "bzcat httpd-2.4.57.tar.bz2" constantly. After 300sec, the successful uncompressions over all 4 loops are summed up and stored in /tmp/counter.
+
+- result with "-cpu qemu64": 96
+- result with "-cpu max": 84
+- result with "-cpu Icelake-Server-noTSX": 44
+Additional information:
+- For "-cpu Icelake-Server-noTSX" on this Thinkpad T590 I get these warnings, I think they are not relevant:
+  qemu-system-x86_64: warning: TCG doesn't support requested feature: CPUID.01H:ECX.pcid [bit 17]
+  qemu-system-x86_64: warning: TCG doesn't support requested feature: CPUID.01H:ECX.tsc-deadline [bit 24]
+  [..]
+- I also looked at Broadwell etc, and all of them seem in the same ballpark.
+  Graph over some emulated architectures: https://fluxcoil.net/files/tmp/gnuplot_cpu-performance-emulated-only.png