14287: Comment multi-dimensional map.

Arvados-DCO-1.1-Signed-off-by: Tom Clegg <tclegg@veritasgenetics.com>

diff --git a/lib/controller/federation/list.go b/lib/controller/federation/list.go
index 43ed2cdbaad3d0750de97238cfc6596a4541a3ee..124946de0ecace85409467315de7d9721c0e2922 100644 (file)
--- a/lib/controller/federation/list.go
+++ b/lib/controller/federation/list.go
@@ -140,6 +140,11 @@ func (conn *Conn) splitListRequest(ctx context.Context, opts arvados.ListOptions
                }
        }
 
+       // Collate UUIDs in matchAllFilters by remote cluster ID --
+       // e.g., todoByRemote["aaaaa"]["aaaaa-4zz18-000000000000000"]
+       // will be true -- and count the total number of UUIDs we're
+       // filtering on, so we can compare it to our max page size
+       // limit.
        nUUIDs := 0
        todoByRemote := map[string]map[string]bool{}
        for uuid := range matchAllFilters {