Usage of eglswapinterval in OpenGL ES2.0. Taken from https://github.com/prabindh/sgxperf/blob/master/sgxperf_gles20_vg.cpp

eglswap

//egl init
int common_eglinit(int testID, int surfaceType, NATIVE_PIXMAP_STRUCT** pNativePixmapPtr)
{
        EGLint iMajorVersion, iMinorVersion;
        EGLint ai32ContextAttribs[] = { EGL_CONTEXT_CLIENT_VERSION, 2, EGL_NONE };
        eglDisplay = eglGetDisplay((int)0);

        if (!eglInitialize(eglDisplay, &iMajorVersion, &iMinorVersion))
                return 1;

        if(testID == 9)
                eglBindAPI(EGL_OPENVG_API);
        else
                eglBindAPI(EGL_OPENGL_ES_API);
        if (!TestEGLError("eglBindAPI"))
                return 1;

        EGLint pi32ConfigAttribs[5];
        pi32ConfigAttribs[0] = EGL_SURFACE_TYPE;
        pi32ConfigAttribs[1] = EGL_WINDOW_BIT | EGL_PIXMAP_BIT;
        pi32ConfigAttribs[2] = EGL_RENDERABLE_TYPE;
        if(testID == 9)
                pi32ConfigAttribs[3] = EGL_OPENVG_BIT;
        else
                pi32ConfigAttribs[3] = EGL_OPENGL_ES2_BIT;
        pi32ConfigAttribs[4] = EGL_NONE;

        int iConfigs;
        if (!eglChooseConfig(eglDisplay, pi32ConfigAttribs, &eglConfig, 1, &iConfigs) || (iConfigs != 1))
        {
                SGXPERF_ERR_printf("Error: eglChooseConfig() failed.\n");
                return 1;
        }
        if(surfaceType == SGXPERF_SURFACE_TYPE_WINDOW)
                eglSurface = eglCreateWindowSurface(eglDisplay, eglConfig, (void*) NULL, NULL);
        else if(surfaceType == SGXPERF_SURFACE_TYPE_PIXMAP_16)
        {
                common_create_native_pixmap(SGXPERF_RGB565,
                                                inTextureWidth, inTextureHeight, pNativePixmapPtr);
                eglSurface = eglCreatePixmapSurface(eglDisplay, eglConfig, *pNativePixmapPtr, NULL);
        }
        else if(surfaceType == SGXPERF_SURFACE_TYPE_PIXMAP_32)
        {
                common_create_native_pixmap(SGXPERF_ARGB8888,
                                                inTextureWidth, inTextureHeight, pNativePixmapPtr);
                eglSurface = eglCreatePixmapSurface(eglDisplay, eglConfig, *pNativePixmapPtr, NULL);
        }
  else
    return 999;

        if (!TestEGLError("eglCreateSurface"))
                return 1;
                
        if(testID == 14) //Create one pixmap surface for context switch latency check
        {
                common_create_native_pixmap(SGXPERF_RGB565,
                                                inTextureWidth, inTextureHeight, pNativePixmapPtr);
                eglSurface2 = eglCreatePixmapSurface(eglDisplay, eglConfig, *pNativePixmapPtr, NULL);
        }         
        if (!TestEGLError("eglCreateSurface"))
                return 1;                

        if(testID == 9)
                eglContext = eglCreateContext(eglDisplay, eglConfig, NULL, NULL);
        else
                eglContext = eglCreateContext(eglDisplay, eglConfig, NULL, ai32ContextAttribs);
        if (!TestEGLError("eglCreateContext"))
                return 1;

        eglMakeCurrent(eglDisplay, eglSurface, eglSurface, eglContext);
        if (!TestEGLError("eglMakeCurrent"))
                return 1;

        eglSwapInterval(eglDisplay, 1);
        if (!TestEGLError("eglSwapInterval"))
                return 1;

        eglQuerySurface(eglDisplay, eglSurface, EGL_WIDTH, &windowWidth);
        eglQuerySurface(eglDisplay, eglSurface, EGL_HEIGHT, &windowHeight);
        
        SGXPERF_printf("Window width=%d, Height=%d\n", windowWidth, windowHeight);

        return 0;
}