From: Gerd Hoffmann <kraxel@redhat.com>
To: qemu-devel@nongnu.org
Subject: [Qemu-devel] vga slow with -enable-kvm
Date: Fri, 07 Nov 2008 10:18:33 +0100 [thread overview]
Message-ID: <491407E9.4040506@redhat.com> (raw)
Hi,
The vga display is very slow when using latest svn with kvm enabled.
Just try to boot any linux kernel with vesafb enabled (vga=0x314 for
800x600@16), enjoy watching the boot messages scroll. Booting without
kvm enabled is *faster*.
Feels like every single screen access is trapped or something like that.
kvm_stat confirms that, there are tons of mmio exits:
[root@zweiblum ~]# kvm_stat -1
efer_reload 0 0
exits 98234706 132054
fpu_reload 6330433 0
halt_exits 104372 0
halt_wakeup 0 0
host_state_reload 96499874 132038
hypercalls 0 0
insn_emulation 94632076 129954
insn_emulation_fail 0 0
invlpg 0 0
io_exits 2627489 1653
irq_exits 239675 397
irq_window 11138 14
largepages 0 0
mmio_exits 93583132 129946
mmu_cache_miss 38079 0
mmu_flooded 37708 0
mmu_pde_zapped 35810 0
mmu_pte_updated 588299 0
mmu_pte_write 647324 0
mmu_recycled 0 0
mmu_shadow_zapped 48191 0
pf_fixed 1211070 1
pf_guest 109462 0
remote_tlb_flush 0 0
request_irq 0 0
signal_exits 164181 402
tlb_flush 728218 44
cheers,
Gerd
next reply other threads:[~2008-11-07 9:18 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-11-07 9:18 Gerd Hoffmann [this message]
2008-11-07 10:17 ` [Qemu-devel] vga slow with -enable-kvm Glauber Costa
2008-11-07 14:02 ` Anthony Liguori
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