Absolutely slow Windows XP SP3 installation

[T-artem]

Host: Linux 4.3.3 vanilla x86-64/Qemu 2.5 i686 (mixed env)
Guest: Windows XP Professional SP3 (i686)

This is my launch string:

$ qemu-system-i386 \
-name "Windows XP Professional SP3" \
-vga std \
-net nic,model=pcnet \
-cpu core2duo \
-smp cores=2 \
-cdrom /tmp/en_winxp_pro_with_sp3_vl.iso \
-hda Windows_XP.qcow \
-boot d \
-net nic \
-net user \
-m 1536 \
-localtime

Console output:

warning: TCG doesn't support requested feature: CPUID.01H:EDX.vme [bit 1]
warning: TCG doesn't support requested feature: CPUID.80000001H:EDX.syscall [bit 11]
warning: TCG doesn't support requested feature: CPUID.80000001H:EDX.lm|i64 [bit 29]
warning: TCG doesn't support requested feature: CPUID.01H:EDX.vme [bit 1]
warning: TCG doesn't support requested feature: CPUID.80000001H:EDX.syscall [bit 11]
warning: TCG doesn't support requested feature: CPUID.80000001H:EDX.lm|i64 [bit 29]

After hitting 35% installation more or less stalls (it actually doesn't but it progresses 1% a minute which is totally unacceptable).

[T-artem (t-artem)]

That was without KVM acceleration, so perhaps it's how it's meant to be.

With KVM everything is fast and smooth.

[Emilio G. Cota (cota)]

For integer workloads such as installing an OS you should expect TCG to be about 12x slower than KVM on average. That is on current master; note that TCG has gotten faster in the last couple of years. See a performance comparison from v2.7.0 to v2.11.0 for SPEC06 here: https://imgur.com/a/5P5zj

I've therefore marked the report as invalid, as I don't think the aforementioned speedups will change your experience dramatically.