A read latency reduction method, applied to a controller, wherein a front end of the controller is connected to a host, and a back end of the controller is connected to a flash array, the flash array comprises a plurality of storage areas, and a plurality of physical locations whose physical characteristics are identical or similar and/or whose read voltage characteristics are identical or similar, are allocated to the same storage area, and the plurality of physical locations of each same storage area correspond to the same read voltage, and the method comprises: receiving, by the controller, a read request sent by the host, wherein the read request comprises location indication information of requested data; obtaining, by the controller, from read voltage management information based on a first physical location indicated by the location indication information, the read voltage corresponding to the first storage area in which the first physical location is located, wherein the first physical location is the physical location of the requested data in the flash array, wherein the read voltage management information comprises the correspondence between storage area and read voltage, and wherein the read voltages in the read voltage management information are dynamically updated; and obtaining, by the controller, the requested data based on the read voltage corresponding to the first storage area, and sending the requested data to the host; wherein dynamically updating the read voltage in the read voltage management information comprises: for any storage area in the plurality of storage areas, when the controller is in a system idle time window or a preset update period is met, determining, by the controller, a first error parameter at the read voltage corresponding to the storage area through active sampling, wherein the first error parameter indicates an error level in the read data; and when the first error parameter is greater than or equal to a first threshold, updating, by the controller, the read voltage corresponding to the storage area in the read voltage management information, characterized in that the dynamic updating additionally comprises: when a second error parameter of the requested data, that is read from the storage area for the first time, is greater than or equal to the first threshold at the read voltage corresponding to the storage area, updating, by the controller, the read voltage corresponding to the storage area in the read voltage management information, wherein the second error parameter indicates an error level in the read requested data. receiving, by the controller, a read request sent by the host, wherein the read request comprises location indication information of requested data; obtaining, by the controller, from read voltage management information based on a first physical location indicated by the location indication information, the read voltage corresponding to the first storage area in which the first physical location is located, wherein the first physical location is the physical location of the requested data in the flash array, wherein the read voltage management information comprises the correspondence between storage area and read voltage, and wherein the read voltages in the read voltage management information are dynamically updated; and obtaining, by the controller, the requested data based on the read voltage corresponding to the first storage area, and sending the requested data to the host; wherein dynamically updating the read voltage in the read voltage management information comprises: for any storage area in the plurality of storage areas, when the controller is in a system idle time window or a preset update period is met, determining, by the controller, a first error parameter at the read voltage corresponding to the storage area through active sampling, wherein the first error parameter indicates an error level in the read data; and when the first error parameter is greater than or equal to a first threshold, updating, by the controller, the read voltage corresponding to the storage area in the read voltage management information, characterized in that the dynamic updating additionally comprises: when a second error parameter of the requested data, that is read from the storage area for the first time, is greater than or equal to the first threshold at the read voltage corresponding to the storage area, updating, by the controller, the read voltage corresponding to the storage area in the read voltage management information, wherein the second error parameter indicates an error level in the read requested data. for any storage area in the plurality of storage areas, when the controller is in a system idle time window or a preset update period is met, determining, by the controller, a first error parameter at the read voltage corresponding to the storage area through active sampling, wherein the first error parameter indicates an error level in the read data; and when the first error parameter is greater than or equal to a first threshold, updating, by the controller, the read voltage corresponding to the storage area in the read voltage management information, characterized in that the dynamic updating additionally comprises: when a second error parameter of the requested data, that is read from the storage area for the first time, is greater than or equal to the first threshold at the read voltage corresponding to the storage area, updating, by the controller, the read voltage corresponding to the storage area in the read voltage management information, wherein the second error parameter indicates an error level in the read requested data.