GXReadVCacheMetric

Syntax

#include <revolution/gx.h>

void GXReadVCacheMetric( u32*         check,
                         u32*         miss,
                         u32*         stall );

Arguments

check	The total number of access hits for the vertex cache.
miss	The total number of cache misses during access to the vertex cache.
stall	The number of GP clock units for which the vertex cache was stalled.

Return Values

None.

Description

The graphics processor (GP) can count many internal events that give detailed information on performance. This function returns Vertex Cache performance counters.

Each call to the GXClearVCacheMetric function resets the counter to zero. GXSetVCacheMetric sets the metric to be measured by the vertex cache performance counter.

Example

u32 chk, miss, stall;
 
 GXSetVCacheMetric(GX_VC_ALL);
 GXClearVCacheMetric();
 
 // Render Object(s)

// wait until objects are rendered
 GXSetDrawSync(0xbeef);
 while (0xbeef != GXReadDrawSync())
     ;
 
 GXReadVCacheMetric(&chk, &miss, &stall);
 
 OSReport("Vertex Cache miss rate:  %f\n", (f32)miss/(f32)chk);

This function reads CPU-accessible registers in the GP and so should not be called in a display list.

Revision History

2006/03/01 Initial version.

CONFIDENTIAL