public void set( long x ) {
    CAT newcat = new CAT(null,4,x);
    // Spin until CAS works
    while( !CAS_cat(_cat,newcat) ) {/*empty*/}
  }
Atomically set the sum of the striped counters to specified value.
 Rather more expensive than a simple store, in order to remain atomic.
jctools-core/src/main/java/org/jctools/maps/ConcurrentAutoTable.java