Improving the lock free mpmc queue

Making the queue growable
Add padding to avoir false sharing
Add sleep() and SwitchToThread() to limit spinning

platform.h

@@ -103,16 +103,22 @@ static double timer_stop(HiResTimer *t) {
 typedef struct {
   atomic_size_t seq;
   FileEntry *data;
+  char pad[64 - sizeof(atomic_size_t) - sizeof(FileEntry *)];
 } MPMCSlot;
 
 typedef struct {
+  atomic_size_t head;
+  char pad1[64];
+  atomic_size_t tail;
+  char pad2[64];
+
   size_t capacity;
   size_t mask;
 
-  MPMCSlot *slots;
+  atomic_size_t committed;
+  size_t commit_step;
 
-  atomic_size_t head;
-  atomic_size_t tail;
+  MPMCSlot *slots;
 } MPMCQueue;
 
 static MPMCQueue g_file_queue;