code: func (f *freelist) reload(p *page) {
  	f.read(p)
  
  	// Build a cache of only pending pages.
  	pcache := make(map[pgid]bool)
  	for _, pendingIDs := range f.pending {
  		for _, pendingID := range pendingIDs {
  			pcache[pendingID] = true
  		}
  	}
  
  	// Check each page in the freelist and build a new available freelist
  	// with any pages not in the pending lists.
  	var a []pgid
  	for _, id := range f.ids {
  		if !pcache[id] {
  			a = append(a, id)
  		}
  	}
  	f.ids = a
  
  	// Once the available list is rebuilt then rebuild the free cache so that
  	// it includes the available and pending free pages.
  	f.reindex()
  }
docs: // reload reads the freelist from a page and filters out pending items.