Why queries are slow when more than one mixed index in query

ConfiguredGraphFactory.open("tenant51").traversal().V().has('_t', 'infra:container').has('_it', gt(123)).limit(100) is taking 400ms while ConfiguredGraphFactory.open("tenant51").traversal().V().has('_it', gt(123)).limit(100) or ConfiguredGraphFactory.open("tenant51").traversal().V().has('t', 'infra:container').limit(100) takes 4 ms @Bo any suggestions ?