Sandisk Technologies Inc.

Western Digital Technologies, Inc.

Rotem Sela

Shay Benisty

Amir Segev

Asher Druck

Shemmer Choresh

Aki Bleyer

Alexander Lemberg

The present disclosure generally relates to read and write operations utilizing barrier commands. Using barrier commands and a snapshot of doorbell states of submission queues (SQs), the necessary write commands to perform a read may be identified and executed to reduce any wait time of the host. As such, host delays during reads and writes are reduced. In absence of a barrier command, the host needs to wait for writes to complete before performing a read. When a barrier command is used, the host needs to wait for the barrier command to complete before performing a read. The controller will execute the post barrier reads only after completing the pre-barrier writes. As will be discussed herein, the controller completes the barrier command as soon as a doorbell snapshot is taken even though the pre-barrier writes may not yet be completed.

Fast execution of barrier command

A data storage device implements a Zoned Namespace (ZNS) storage architecture. The data storage device delays the execution of write commands that are received out of sequence instead of rejecting the write commands. The write commands that are received out of sequence are reordered according to a logical block address (LBA) associated with each write command. The data storage device also checks for deadlock conditions that may arise due to the execution of the write commands being delayed and/or due to the write commands being reordered.

Processing commands in a sequential write required zone model

A data storage device includes a memory device and a controller coupled to the memory device. The controller is configured to maintain a plurality of virtual pools, wherein each virtual pool corresponds with an logical block address (LBA) range, update a counter of a virtual pool, wherein the counter corresponds to a health of the LBA range, and select, based on the counter, the virtual pool to program data to. The controller is further configured to maintain a counter for each application having data programmed to the virtual pool, where the counter is increased for each write operation to the virtual pool. When the counter equals or exceeds a threshold value, the controller is configured to send a warning to each application associated with the virtual pool having the counter that equals or exceeds the threshold value.

Virtual block pools for protecting device health

The present disclosure generally relates to recognizing a violation of an expected write amplification (WAF) rate and informing a host device of the violation so that the host device may take corrective action and ensure the data storage device does not reach end of life (EOL) earlier than expected. The host can provide the data storage device with an expected lifetime and may additionally provide a benchmark WAF rate. The data storage device compares the actual WAF rate to the benchmark WAF rate and notifies the host device of any violation where the actual WAF rate exceeds the benchmark WAF rate.

Recognition and report of expected write amplification violation

The present disclosure generally relates to utilizing the host clock signal frequency to determine whether to operate in the default pulse width modulation (PWM) link startup sequence (LSS), be changed to high speed (HS) LSS by a host device capable of operating in either PWM LSS or HS LSS, or ignore the data storage device attributes of operating in PWM LSS and instead operate according to HS LSS. In so doing, the data storage device is adaptable to work with older generation UFS host devices as well as current and future generation UFS host devices.

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Sunnyvale, CA, United States of America

Rotem Sela