Graphql subscription request and dataloaders

[coolbharat78]

    fun subscription(
       args
        dataFetchingEnvironment: DataFetchingEnvironment,
    ): Flux<Response> {
        log.debug { "pageSize: $pageIndex $pageSize" }

        return r2dbcCall.execute().buffer(batchSize)
            .concatMap { accounts ->
                val gqlAccountList =
                    accounts.map {
                        it.toGqlObject()
                    }
                Flux.just(
                    Response(
                        queryObject = cycleCode.toString(),
                        accounts = gqlAccountList,
                    ),
                )
            }
    }

This is related to graphql subscription request.

In the above request the r2dbc is sending a stream of accounts and I buffer 100 and create a response with 100 accounts expecting that dataloaders will be called in once per batch of 100 with 100 accounts as keys but why is dataloader called sequentially only with one account as key?