Re: Working on an entry-level project

Jindrich Makovicka
2007-10-13T21:16:40Z

[-- Attachment #1: Type: text/plain, Size: 1031 bytes --]

On Sat, 13 Oct 2007 12:39:15 +0200
Izik Eidus <izike-atKUWr5tajBWk0Htik3J/w@public.gmane.org> wrote:

> Cam Macdonell wrote:
> > Dor Laor wrote:
> >> Cam Macdonell wrote:
> >>>
> >> It's a simple test, when there are keyboard/mouse/display changes
> >> keep the refresh rate high. When there are no changes start
> >> decrease the rate until a minimum
> >> reached. The performance benefit should also be checked since if
> >> it minimal there's no use for this optimization.

Even if it doesn't bring any performance benefits, I think that having a
smoothly moving mouse cursor is useful, if you intend to run a desktop
operating system inside QEMU. The current refresh rate QEMU uses is
quite low and the mouse interactivity is poor in comparison with vmware
+ vmware tools.

I am currently using the attached patch to improve the mouse
interactivity - it shortens the screen refresh interval to 10 ms
when the mouse or keyboard is active, and returns to 30 ms after a 100
ms inactivity period.

Regards,
--
Jindrich Makovicka

[-- Attachment #2: kvm-45.diff --]
[-- Type: text/x-patch, Size: 3667 bytes --]

diff -ur kvm-45.orig/qemu/sdl.c kvm-45/qemu/sdl.c
--- kvm-45.orig/qemu/sdl.c 2007-10-02 10:36:33.000000000 +0200
+++ kvm-45/qemu/sdl.c 2007-10-07 08:32:38.000000000 +0200
@@ -47,6 +47,8 @@
static int guest_cursor = 0;
static int guest_x, guest_y;
static SDL_Cursor *guest_sprite = 0;
+static int decimate_counter = 0;
+static int idle_counter = 0;

static void sdl_update(DisplayState *ds, int x, int y, int w, int h)
{
@@ -347,17 +349,24 @@
vga_hw_update();
}

+#define SDL_IDLE_THRESHOLD 10
+#define SDL_DECIMATE 3
+
static void sdl_refresh(DisplayState *ds)
{
SDL_Event ev1, *ev = &ev1;
int mod_state;
+ int was_idle = 1;

if (last_vm_running != vm_running) {
last_vm_running = vm_running;
sdl_update_caption();
}

- vga_hw_update();
+ if (idle_counter < SDL_IDLE_THRESHOLD || decimate_counter == 0)
+ vga_hw_update();
+
+ decimate_counter = (decimate_counter + 1) % SDL_DECIMATE;

while (SDL_PollEvent(ev)) {
switch (ev->type) {
@@ -366,6 +375,7 @@
break;
case SDL_KEYDOWN:
case SDL_KEYUP:
+ was_idle = 0;
if (ev->type == SDL_KEYDOWN) {
if (!alt_grab) {
mod_state = (SDL_GetModState() & gui_grab_code) ==
@@ -476,6 +486,7 @@
}
break;
case SDL_MOUSEMOTION:
+ was_idle = 0;
if (gui_grab || kbd_mouse_is_absolute() ||
absolute_enabled) {
sdl_send_mouse_event(0);
@@ -483,6 +494,7 @@
break;
case SDL_MOUSEBUTTONDOWN:
case SDL_MOUSEBUTTONUP:
+ was_idle = 0;
{
SDL_MouseButtonEvent *bev = &ev->button;
if (!gui_grab && !kbd_mouse_is_absolute()) {
@@ -515,6 +527,13 @@
break;
}
}
+
+ if (was_idle) {
+ if (idle_counter < SDL_IDLE_THRESHOLD)
+ idle_counter++;
+ } else {
+ idle_counter = 0;
+ }
}

static void sdl_fill(DisplayState *ds, int x, int y, int w, int h, uint32_t c)
@@ -627,6 +646,7 @@
ds->dpy_fill = sdl_fill;
ds->mouse_set = sdl_mouse_warp;
ds->cursor_define = sdl_mouse_define;
+ ds->refresh_interval = 10;

sdl_resize(ds, 640, 400);
sdl_update_caption();
diff -ur kvm-45.orig/qemu/vl.c kvm-45/qemu/vl.c
--- kvm-45.orig/qemu/vl.c 2007-10-02 10:36:33.000000000 +0200
+++ kvm-45/qemu/vl.c 2007-10-07 08:34:01.000000000 +0200
@@ -142,7 +142,7 @@
#define DEFAULT_RAM_SIZE 128
#endif
/* in ms */
-#define GUI_REFRESH_INTERVAL 30
+#define DEFAULT_GUI_REFRESH_INTERVAL 30

/* Max number of USB devices that can be specified on the commandline. */
#define MAX_USB_CMDLINE 8
@@ -4918,6 +4918,7 @@
ds->dpy_update = dumb_update;
ds->dpy_resize = dumb_resize;
ds->dpy_refresh = dumb_refresh;
+ ds->refresh_interval = DEFAULT_GUI_REFRESH_INTERVAL;
}

/***********************************************************/
@@ -6913,7 +6914,7 @@
{
DisplayState *ds = opaque;
ds->dpy_refresh(ds);
- qemu_mod_timer(ds->gui_timer, GUI_REFRESH_INTERVAL + qemu_get_clock(rt_clock));
+ qemu_mod_timer(ds->gui_timer, display_state.refresh_interval + qemu_get_clock(rt_clock));
}

struct vm_change_state_entry {
diff -ur kvm-45.orig/qemu/vl.h kvm-45/qemu/vl.h
--- kvm-45.orig/qemu/vl.h 2007-10-02 10:36:33.000000000 +0200
+++ kvm-45/qemu/vl.h 2007-10-07 08:33:36.000000000 +0200
@@ -970,6 +970,7 @@
int height;
void *opaque;
QEMUTimer *gui_timer;
+ int refresh_interval;

void (*dpy_update)(struct DisplayState *s, int x, int y, int w, int h);
void (*dpy_resize)(struct DisplayState *s, int w, int h);

[-- Attachment #3: Type: text/plain, Size: 314 bytes --]

-------------------------------------------------------------------------
This SF.net email is sponsored by: Splunk Inc.
Still grepping through log files to find problems? Stop.
Now Search log events and configuration files using AJAX and a browser.
Download your FREE copy of Splunk now >> http://get.splunk.com/

[-- Attachment #4: Type: text/plain, Size: 186 bytes --]

_______________________________________________
kvm-devel mailing list
kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org