Each search request allows the client to specify the size limit and time limit that should be used for that operation.
If the client requests a size limit of zero, then that indicates that the client does not want to impose any limit and the search request is processed using whatever size limit imposes for that client. If the client requests a nonzero size limit and that requested size limit is lower than what the server would otherwise impose, then the client-requested size limit is used. If the client requests a size limit that is higher than what the server would otherwise impose, then the server-imposed limit is used.
The same logic applies to the requested time limit. That is, the time limit from the search request is used if it is lower than what the server would have otherwise imposed. Otherwise, the server’s limit is used.