Re: [Qemu-devel] Re: QEMU-KVM and video performance - Update

2011-02-17 Thread Gerhard Wiesinger
Hello, Some update on this issue, archive: http://www.mail-archive.com/kvm@vger.kernel.org/msg32600.html Seems to be that cirrus VGA is now ok (1000MB/s up to 2000MB/s). But cirrus has only 320x200x256colors (Mode 13h) mode implemented in VESA BIOS. VMWare and std VGA still have the

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-05-12 Thread Gerhard Wiesinger
On Mon, 10 May 2010, Avi Kivity wrote: On 05/09/2010 10:35 PM, Gerhard Wiesinger wrote: For 256 color more the first priority is to find out why direct mapping is not used. I'd suggest tracing the code that makes this decision (in hw/*vga.c) and seeing if it's right or not. I think

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-05-12 Thread Avi Kivity
On 05/12/2010 09:14 AM, Gerhard Wiesinger wrote: On Mon, 10 May 2010, Avi Kivity wrote: On 05/09/2010 10:35 PM, Gerhard Wiesinger wrote: For 256 color more the first priority is to find out why direct mapping is not used. I'd suggest tracing the code that makes this decision (in

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-05-12 Thread Jamie Lokier
Gerhard Wiesinger wrote: On Wed, 21 Apr 2010, Jamie Lokier wrote: Gerhard Wiesinger wrote: Hmmm. I'm very new to QEMU and KVM but at least accessing the virtual HW of QEMU even from KVM must be possible (e.g. memory and port accesses are done on nearly every virtual device) and therefore

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-05-12 Thread Jamie Lokier
Gerhard Wiesinger wrote: Can one switch to the old software vmm in VMWare? Perhaps you can install a very old version of VMWare. Maybe run it under KVM ;-) That was one of the reasons why I was looking for alternatives for graphical DOS programs. Overall summary so far: 1.) QEMU without

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-05-10 Thread Avi Kivity
On 05/09/2010 10:35 PM, Gerhard Wiesinger wrote: Please run kvm_stat and report output for both tests to confirm. See below. 2nd column is per second statistic when running the test. efer_reload 0 0 exits 18470836 554582 fpu_reload

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-05-09 Thread Gerhard Wiesinger
On Thu, 22 Apr 2010, Avi Kivity wrote: On 04/22/2010 09:04 AM, Gerhard Wiesinger wrote: On Wed, 21 Apr 2010, Avi Kivity wrote: On 04/21/2010 09:50 PM, Gerhard Wiesinger wrote: I don't think changing VGA window is a problem because there are 500.000-1Mio changes/s possible. 1MB/s, 500k-1M

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-04-22 Thread Gerhard Wiesinger
On Wed, 21 Apr 2010, Avi Kivity wrote: On 04/21/2010 09:50 PM, Gerhard Wiesinger wrote: I don't think changing VGA window is a problem because there are 500.000-1Mio changes/s possible. 1MB/s, 500k-1M changes/s Coincidence? Is it taking a page fault or trap on every write? To

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-04-22 Thread Gerhard Wiesinger
On Wed, 21 Apr 2010, Jamie Lokier wrote: Gerhard Wiesinger wrote: Hmmm. I'm very new to QEMU and KVM but at least accessing the virtual HW of QEMU even from KVM must be possible (e.g. memory and port accesses are done on nearly every virtual device) and therefore I'm ending in C code in the

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-04-22 Thread Avi Kivity
On 04/22/2010 08:37 AM, Gerhard Wiesinger wrote: On Wed, 21 Apr 2010, Avi Kivity wrote: On 04/21/2010 09:14 PM, Gerhard Wiesinger wrote: Can you explain which code files/functions of KVM is involved in handling VGA memory window and page switching through the port write to the VGA window

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-04-22 Thread Avi Kivity
On 04/22/2010 09:04 AM, Gerhard Wiesinger wrote: On Wed, 21 Apr 2010, Avi Kivity wrote: On 04/21/2010 09:50 PM, Gerhard Wiesinger wrote: I don't think changing VGA window is a problem because there are 500.000-1Mio changes/s possible. 1MB/s, 500k-1M changes/s Coincidence? Is it taking

Re: QEMU-KVM and video performance

2010-04-21 Thread Avi Kivity
On 04/19/2010 10:14 PM, Gerhard Wiesinger wrote: Hello, Finally I got QEMU-KVM to work but video performance under DOS is very low (QEMU 0.12.3 stable and QEMU GIT master branch is fast, QEMU KVM is slow) I'm measuring 2 performance critical video performance parameters: 1.) INT 10h,

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-04-21 Thread Jamie Lokier
Avi Kivity wrote: On 04/19/2010 10:14 PM, Gerhard Wiesinger wrote: Hello, Finally I got QEMU-KVM to work but video performance under DOS is very low (QEMU 0.12.3 stable and QEMU GIT master branch is fast, QEMU KVM is slow) I'm measuring 2 performance critical video performance

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-04-21 Thread Avi Kivity
On 04/21/2010 01:08 PM, Jamie Lokier wrote: Avi Kivity wrote: On 04/19/2010 10:14 PM, Gerhard Wiesinger wrote: Hello, Finally I got QEMU-KVM to work but video performance under DOS is very low (QEMU 0.12.3 stable and QEMU GIT master branch is fast, QEMU KVM is slow) I'm measuring 2

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-04-21 Thread Gerhard Wiesinger
On Wed, 21 Apr 2010, Avi Kivity wrote: On 04/19/2010 10:14 PM, Gerhard Wiesinger wrote: Hello, Finally I got QEMU-KVM to work but video performance under DOS is very low (QEMU 0.12.3 stable and QEMU GIT master branch is fast, QEMU KVM is slow) I'm measuring 2 performance critical video

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-04-21 Thread Gerhard Wiesinger
On Wed, 21 Apr 2010, Avi Kivity wrote: On 04/21/2010 01:08 PM, Jamie Lokier wrote: Avi Kivity wrote: On 04/19/2010 10:14 PM, Gerhard Wiesinger wrote: Hello, Finally I got QEMU-KVM to work but video performance under DOS is very low (QEMU 0.12.3 stable and QEMU GIT master branch is fast,

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-04-21 Thread Jamie Lokier
Avi Kivity wrote: Writes to vga in 16-color mode don't change set a memory location to a value, instead they change multiple memory locations. While code is just writing to the VGA memory, not reading(*) and not touching the VGA I/O register that control the write latches, is it possible in

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-04-21 Thread Jamie Lokier
Gerhard Wiesinger wrote: Would it be possible to handle these writes through QEMU directly (without KVM), because performance is there very well (looking at the code there is some pointer arithmetic and some memory write done)? I've noticed extremely slow VGA performance too, when

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-04-21 Thread Gerhard Wiesinger
On Wed, 21 Apr 2010, Jamie Lokier wrote: Gerhard Wiesinger wrote: Would it be possible to handle these writes through QEMU directly (without KVM), because performance is there very well (looking at the code there is some pointer arithmetic and some memory write done)? I've noticed extremely

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-04-21 Thread Avi Kivity
On 04/21/2010 09:14 PM, Gerhard Wiesinger wrote: Can you explain which code files/functions of KVM is involved in handling VGA memory window and page switching through the port write to the VGA window register (or is that part handled through QEMU), so a little bit architecture explaination

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-04-21 Thread Avi Kivity
On 04/21/2010 09:39 PM, Jamie Lokier wrote: Avi Kivity wrote: Writes to vga in 16-color mode don't change set a memory location to a value, instead they change multiple memory locations. While code is just writing to the VGA memory, not reading(*) and not touching the VGA I/O

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-04-21 Thread Avi Kivity
On 04/21/2010 09:50 PM, Gerhard Wiesinger wrote: I don't think changing VGA window is a problem because there are 500.000-1Mio changes/s possible. 1MB/s, 500k-1M changes/s Coincidence? Is it taking a page fault or trap on every write? To clarify: Memory Performance writing to segmen

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-04-21 Thread Jamie Lokier
Avi Kivity wrote: On 04/21/2010 09:39 PM, Jamie Lokier wrote: Avi Kivity wrote: Writes to vga in 16-color mode don't change set a memory location to a value, instead they change multiple memory locations. While code is just writing to the VGA memory, not reading(*) and not

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-04-21 Thread Jamie Lokier
Gerhard Wiesinger wrote: Hmmm. I'm very new to QEMU and KVM but at least accessing the virtual HW of QEMU even from KVM must be possible (e.g. memory and port accesses are done on nearly every virtual device) and therefore I'm ending in C code in the QEMU hw/*.c directory. Therefore also the

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-04-21 Thread Gerhard Wiesinger
On Wed, 21 Apr 2010, Avi Kivity wrote: On 04/21/2010 09:14 PM, Gerhard Wiesinger wrote: Can you explain which code files/functions of KVM is involved in handling VGA memory window and page switching through the port write to the VGA window register (or is that part handled through QEMU), so

Re: [Qemu-devel] Re: QEMU-KVM and video performance

2010-04-21 Thread Gerhard Wiesinger
On Wed, 21 Apr 2010, Avi Kivity wrote: On 04/21/2010 09:39 PM, Jamie Lokier wrote: Avi Kivity wrote: Writes to vga in 16-color mode don't change set a memory location to a value, instead they change multiple memory locations. While code is just writing to the VGA memory, not reading(*) and

QEMU-KVM and video performance

2010-04-19 Thread Gerhard Wiesinger
Hello, Finally I got QEMU-KVM to work but video performance under DOS is very low (QEMU 0.12.3 stable and QEMU GIT master branch is fast, QEMU KVM is slow) I'm measuring 2 performance critical video performance parameters: 1.) INT 10h, function AX=4F05h (set same window/set window/get