Selectively throttling host reads for read disturbs in non-volatile memory system

A non-volatile memory controller for controlling access to non-volatile memory in a non-volatile memory system, the non-volatile memory controller comprising:

• a host interface for receiving, from a host device external to the non-volatile memory system, a read request to read data from the non-volatile memory system;
• one or more processors;
• and
• memory storing one or more programs for execution by the one or more processors, the one or more programs including instructions for:
• identifying a storage location in the non-volatile memory system corresponding to data requested by the read request received from the host device;
• determining if the identified storage location satisfies predefined read disturb criteria;
• in accordance with a determination that the identified storage location does not satisfy the predefined read disturb criteria, initiating execution of a read operation corresponding to the read request on the identified storage location;
• and
• in accordance with a determination that the identified storage location satisfies the predefined read disturb criteria;
• determining if the identified storage location satisfies predefined non-activity criteria for a predefined time period;
• and
• in accordance with a determination that the identified storage location satisfies predefined non-activity criteria for the predefined time period:
• enqueuing a read command corresponding to the read request to perform the read operation on the identified storage location for deferred execution;
• and
• initiating execution of read operations corresponding to the enqueued read command and other enqueued read commands at a predefined rate, wherein the predefined rate has a predefined ratio with the predefined time period.

A non-volatile memory system comprising:

• means for receiving, from a host device external to the non-volatile memory system, a read request to read data from a non-volatile memory in the non-volatile memory system;
• means for identifying a storage location in the non-volatile memory corresponding to data requested by the read request received from the host device;
• means for determining if the identified storage location satisfies predefined read disturb criteria and, in accordance with a determination that the identified storage location does not satisfy the predefined read disturb criteria, for initiating execution of a read operation corresponding to the read request on the identified storage location;
• and
• means for, in accordance with a determination that the identified storage location satisfies the predefined read disturb criteria:
• determining if the identified storage location satisfies predefined non-activity criteria for a predefined time period;
• and
• in accordance with a determination that the identified storage location satisfies predefined non-activity criteria for the predefined time period:
• enqueuing a read command corresponding to the read request to perform the read operation on the identified storage location for deferred execution;
• and
• initiating execution of read operations corresponding to the enqueued read command and other enqueued read commands at a predefined rate, wherein the predefined rate has a predefined ratio with the predefined time period.