saver := z.serverPools[o.pool].sets[o.set]

	// Disconnect from call above, but cancel on exit.
	listCtx, cancel := context.WithCancel(GlobalContext)
	saveCh := make(chan metaCacheEntry, metacacheBlockSize)
	inCh := make(chan metaCacheEntry, metacacheBlockSize)
	outCh := make(chan metaCacheEntry, o.Limit)

	filteredResults := o.gatherResults(ctx, outCh)

	mc := o.newMetacache()

	dataScannerCompactLeastObject    = 500                              // Compact when there is less than this many objects in a branch.
	dataScannerCompactAtChildren     = 10000                            // Compact when there are this many children in a branch.
	dataScannerCompactAtFolders      = dataScannerCompactAtChildren / 4 // Compact when this many subfolders in a single folder.