Remove fine-grained timing from narrow-phase collision functions, del…

…ete `mjTIMER_COL_MID`.

PiperOrigin-RevId: 599225419
Change-Id: Ieca166753c20a0abf660e2821b2844dda8758951

doc/changelog.rst

@@ -9,17 +9,20 @@ General
 ^^^^^^^
 1. Improved the :ref:discardvisual<compiler-discardvisual> compiler flag, which now discards all visual-only assets. See
    :ref:discardvisual<compiler-discardvisual> for details.
+2. Removed the :ref:`timer<mjtTimer>` for midphase colllision detection, it is now folded in with the narrowphase
+   timer. This is because timing the two phases seperately required fine-grained timers inside the collision
+   functions; these functions are so small and fast that the timer itself was incurring a measurable cost.
 
 MJX
 ^^^
-2. Added :ref:`dyntype<actuator-general-dyntype>` ``filterexact``.
-3. Added :at:`site` transmission.
-4. Updated MJX colab tutorial with more stable quadruped environment.
-5. Added ``mjx.ray`` which mirrors :ref:`mj_ray` for planes, spheres, capsules, boxes, and meshes.
+3. Added :ref:`dyntype<actuator-general-dyntype>` ``filterexact``.
+4. Added :at:`site` transmission.
+5. Updated MJX colab tutorial with more stable quadruped environment.
+6. Added ``mjx.ray`` which mirrors :ref:`mj_ray` for planes, spheres, capsules, boxes, and meshes.
 
 Bug fixes
 ^^^^^^^^^
-6. Fixed a bug that prevented the use of pins with plugins if flexes are not in the worldbody. Fixes
+7. Fixed a bug that prevented the use of pins with plugins if flexes are not in the worldbody. Fixes
    :github:issue:`1270`.
 7. Fixed a bug in the :ref:`muscle model<CMuscle>` that led to non-zero values outside the lower
    bound of the length range. Fixes :github:issue:`1342`.

doc/includes/references.h

@@ -75,7 +75,6 @@ typedef enum mjtTimer_ {     // internal timers
 
   // breakdown of mj_collision
   mjTIMER_COL_BROAD,         // broadphase
-  mjTIMER_COL_MID,           // midphase
   mjTIMER_COL_NARROW,        // narrowphase
 
   mjNTIMER                   // number of timers

include/mujoco/mjdata.h

@@ -87,7 +87,6 @@ typedef enum mjtTimer_ {     // internal timers
 
   // breakdown of mj_collision
   mjTIMER_COL_BROAD,         // broadphase
-  mjTIMER_COL_MID,           // midphase
   mjTIMER_COL_NARROW,        // narrowphase
 
   mjNTIMER                   // number of timers

introspect/enums.py

@@ -458,9 +458,8 @@
              ('mjTIMER_POS_MAKE', 11),
              ('mjTIMER_POS_PROJECT', 12),
              ('mjTIMER_COL_BROAD', 13),
-             ('mjTIMER_COL_MID', 14),
-             ('mjTIMER_COL_NARROW', 15),
-             ('mjNTIMER', 16),
+             ('mjTIMER_COL_NARROW', 14),
+             ('mjNTIMER', 15),
          ]),
      )),
     ('mjtCatBit',

introspect/structs.py

@@ -4154,7 +4154,7 @@
                  name='timer',
                  type=ArrayType(
                      inner_type=ValueType(name='mjTimerStat'),
-                     extents=(16,),
+                     extents=(15,),
                  ),
                  doc='timer statistics',
              ),

sample/testspeed.cc

@@ -278,7 +278,7 @@ int main(int argc, char** argv) {
 
     // components of mjTIMER_POS_COLLISION
     if (i == mjTIMER_POS_COLLISION) {
-      for (int j : {mjTIMER_COL_BROAD, mjTIMER_COL_MID, mjTIMER_COL_NARROW}) {
+      for (int j : {mjTIMER_COL_BROAD, mjTIMER_COL_NARROW}) {
         int number = d[0]->timer[j].number;
         mjtNum jstep = number ? d[0]->timer[j].duration/number : 0.0;
         mjtNum percent = number ? 100*jstep/tstep : 0.0;

src/engine/engine_collision_driver.c

@@ -291,12 +291,9 @@ void mj_collision(const mjModel* m, mjData* d) {
   unsigned int last_signature = -1;
   TM_END(mjTIMER_COL_BROAD);
 
-  // midphase collision detector
+  // narrowphase and midphase collision detector
   TM_RESTART;
 
-  // save current narrowphase duration
-  mjtNum tmNarrow = d->timer[mjTIMER_COL_NARROW].duration;
-
   // process bodyflex pairs returned by broadphase, merge with predefined geom pairs
   int pairadr = 0;
   for (int i=0; i < nbfpair; i++) {
@@ -471,14 +468,8 @@ void mj_collision(const mjModel* m, mjData* d) {
     }
   }
 
-  // end midphase timer
-  TM_END(mjTIMER_COL_MID);
-
-  // subtract nested narrowphase timing from midphase timer
-  d->timer[mjTIMER_COL_MID].duration -= (d->timer[mjTIMER_COL_NARROW].duration - tmNarrow);
-
-  // increment narrowphase counter
-  d->timer[mjTIMER_COL_NARROW].number++;
+  // end narrowphase and midphase timer
+  TM_END(mjTIMER_COL_NARROW);
 
   mj_freeStack(d);
   TM_END1(mjTIMER_POS_COLLISION);
@@ -1444,8 +1435,6 @@ static void mj_makeCapsule(const mjModel* m, mjData* d, int f, const int vid[2],
 
 // test two geoms for collision, apply filters, add to contact list
 void mj_collideGeoms(const mjModel* m, mjData* d, int g1, int g2) {
-  TM_START;
-
   int num, type1, type2, condim;
   mjtNum margin, gap, friction[5], solref[mjNREF], solimp[mjNIMP];
   mjtNum solreffriction[mjNREF] = {0};
@@ -1635,9 +1624,6 @@ void mj_collideGeoms(const mjModel* m, mjData* d, int g1, int g2) {
 
   // move arena pointer back to the end of the contact array
   resetArena(d);
-
-  // add duration without incrementing counter
-  TM_ADD(mjTIMER_COL_NARROW);
 }
 
 
@@ -1850,8 +1836,6 @@ void mj_collideFlexSAP(const mjModel* m, mjData* d, int f) {
 
 // test a geom and an elem for collision, add to contact list
 void mj_collideGeomElem(const mjModel* m, mjData* d, int g, int f, int e) {
-  TM_START;
-
   mjtNum margin = mj_assignMargin(m, mju_max(m->geom_margin[g], m->flex_margin[f]));
   int dim = m->flex_dim[f], type = m->geom_type[g];
   int num;
@@ -1965,17 +1949,12 @@ void mj_collideGeomElem(const mjModel* m, mjData* d, int g, int f, int e) {
 
   // move arena pointer back to the end of the contact array
   resetArena(d);
-
-  // add duration without incrementing counter
-  TM_ADD(mjTIMER_COL_NARROW);
 }
 
 
 
 // test two elems for collision, add to contact list
 void mj_collideElems(const mjModel* m, mjData* d, int f1, int e1, int f2, int e2) {
-  TM_START;
-
   mjtNum margin = mj_assignMargin(m, mju_max(m->flex_margin[f1], m->flex_margin[f2]));
   int dim1 = m->flex_dim[f1], dim2 = m->flex_dim[f2];
   int num;
@@ -2070,9 +2049,6 @@ void mj_collideElems(const mjModel* m, mjData* d, int f1, int e1, int f2, int e2
 
   // move arena pointer back to the end of the contact array
   resetArena(d);
-
-  // add duration without incrementing counter
-  TM_ADD(mjTIMER_COL_NARROW);
 }
 
 

src/engine/engine_support.c

@@ -89,7 +89,6 @@ const char* mjTIMERSTRING[mjNTIMER]= {
   "pos_make",
   "pos_project",
   "col_broadphase",
-  "col_midphase",
   "col_narrowphase"
 };
 

unity/Runtime/Bindings/MjBindings.cs

@@ -138,9 +138,8 @@ public enum mjtTimer : int{
   mjTIMER_POS_MAKE = 11,
   mjTIMER_POS_PROJECT = 12,
   mjTIMER_COL_BROAD = 13,
-  mjTIMER_COL_MID = 14,
-  mjTIMER_COL_NARROW = 15,
-  mjNTIMER = 16,
+  mjTIMER_COL_NARROW = 14,
+  mjNTIMER = 15,
 }
 public enum mjtDisableBit : int{
   mjDSBL_CONSTRAINT = 1,
@@ -769,7 +768,6 @@ public unsafe struct mjData_ {
   public mjTimerStat_ timer12;
   public mjTimerStat_ timer13;
   public mjTimerStat_ timer14;
-  public mjTimerStat_ timer15;
   public mjSolverStat_ solver0;
   public mjSolverStat_ solver1;
   public mjSolverStat_ solver2;