# US 2021/0334201 A1 · Storage Devices Having Minimum Write Sizes Of Data

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2021/0334201 A1
- Document ID: US20210334201A1
- Status: Published application
- Kind: A1
- Application number: 16/858,339
- Filed: 2020-04-24
- Published: 2021-10-28
- Earliest claimed: 2020-04-24
- Assignees: Western Digital Technologies, Inc.
- Applicants: Western Digital Technologies, Inc.
- Inventors: Alan D. BENNETT; Daniel L. HELMICK; Liam PARKER; Sergey Anatolievich GOROBETS; Peter GRAYSON
- Web page: https://patentgrep.com/patent/US20210334201A1

## CPC

- G06F 12/0246: {in block erasable memory, e.g. flash memory}
- G06F 11/1048: {using arrangements adapted for a specific error detection or correction feature}
- G06F 11/1068: {in sector programmable memories, e.g. flash disk (G06F11/1072 takes precedence)}
- G06F 11/1076: {Parity data used in redundant arrays of independent storages, e.g. in RAID systems}
- G06F 11/3037: {where the computing system component is a memory, e.g. virtual memory, cache (accessing, addressing or allocating within memory systems or architectures G06F12/00; checking stores for correct operation G11C29/00)}
- G06F 12/0882: Page mode
- G06F 13/1668: {Details of memory controller}
- G06F 3/0619: {in relation to data integrity, e.g. data losses, bit errors}
- G06F 3/065: {Replication mechanisms}
- G06F 3/0688: {Non-volatile semiconductor memory arrays}
- G06F 2212/7202: Allocation control and policies
- G06F 2212/7207: management of metadata or control data
- G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N)

## Abstract

The present disclosure generally relates to methods of operating storage devices. The storage device comprises a controller and a storage unit divided into a plurality of streams. The storage unit comprises a plurality of dies, where each die comprises two planes. One erase block from each plane of a die is selected for stream formation. Each erase block comprises a plurality of wordlines. A stream comprises one or two dies dedicated to storing parity data and a plurality of dies dedicated to storing user data. The stream further comprises space devoted for controller metadata. The storage device restricts a host device to send write commands in a minimum write size to increase programming efficiency. The minimum write size equals one wordline from one erase block from each plane of each die in the stream dedicated to storing user data minus the space dedicated to metadata.

## Claims

### Claim 1

A storage device, comprising:
a non-volatile storage unit, wherein a capacity of the non-volatile storage unit is divided into a plurality of streams, and wherein the non-volatile storage unit comprises a plurality of dies, each of the plurality of dies comprising a plurality of erase blocks, and each of the erase blocks comprising a plurality of wordlines; and
a controller coupled to the non-volatile storage unit, wherein the controller is configured to:
determine a minimum write size for commands to write data received from a host device, wherein the minimum write size is determined based on a number of erase blocks in a stream dedicated to storing user data, a pages per cell of the wordlines of each erase block, a number of wordlines in each erase block, and an amount of space dedicated to storing metadata of the storage device; and
receive the commands to write data from the host device in the minimum write size, or
aggregate one or more smaller commands to write data received from the host device having a size smaller than the minimum write size until the minimum write size is reached.

### Claim 2 (depends on 1)

The storage device of claim 1, wherein one or more streams of the plurality of streams comprise the same number of erase blocks and have a same writable capacity, and wherein one or more streams of the plurality of streams comprise a different number of erase blocks and have a different writable capacity.

### Claim 3 (depends on 1)

The storage device of claim 1, wherein the minimum write size is determined to write two full wordlines in each die of the stream minus the amount of space dedicated to storing metadata.

### Claim 4 (depends on 3)

The storage device of claim 3, wherein each die of the stream comprises two planes, and wherein the minimum write size is determined to write to one full wordline in each plane of each die of the stream minus the amount of space dedicated to storing metadata.

### Claim 5 (depends on 1)

The storage device of claim 1, wherein a portion of each wordline comprises the amount of space dedicated to storing metadata.

### Claim 6 (depends on 1)

The storage device of claim 1, wherein a portion of each erase block comprises the amount of space dedicated to storing metadata.

### Claim 7 (depends on 1)

The storage device of claim 1, wherein at least one die in each stream is dedicated to storing die failure protection data.

### Claim 8

A storage device, comprising:
a non-volatile storage unit, wherein a capacity of the non-volatile storage unit is divided into a plurality of streams, and wherein the non-volatile storage unit comprises a plurality of dies, each of the plurality of dies comprising a plurality of planes, each of the planes comprising a plurality of erase blocks, and each of the erase blocks comprising a plurality of wordlines; and
a controller coupled to the non-volatile storage unit, wherein the controller is configured to:
calculate a minimum write size for commands to write data received from a host device, wherein the minimum write size is calculated to write a full wordline size of one erase block of each plane of each die dedicated to storing user data within a stream; and
restrict the host device through a verbal agreement or a handshake agreement to send the commands to write data in the minimum write size.

### Claim 9 (depends on 8)

The storage device of claim 8, wherein the minimum write size is calculated based on a pages per cell of the plurality of wordlines.

### Claim 10 (depends on 8)

The storage device of claim 8, wherein a portion of each stream comprises a metadata capacity for the storage device to write to.

### Claim 11 (depends on 10)

The storage device of claim 10, wherein the minimum write size is calculated to account for the metadata capacity.

### Claim 12 (depends on 8)

The storage device of claim 8, wherein the controller is further configured to:
receive one or more write commands from the host device in a size smaller than the minimum write size;
hold the one or more write commands until the one or more write commands aggregate to the minimum write size; and
write the one or more write commands to the non-volatile storage unit once the one or more write commands are aggregated to the minimum write size.

### Claim 13 (depends on 8)

The storage device of claim 8, wherein each stream comprises a plurality of user data dies dedicated to storing user data, a first parity die, and a second parity die.

### Claim 14 (depends on 13)

The storage device of claim 13, wherein the first parity die is dedicated to storing p-parity data and the second parity die is dedicated to storing q-parity data.

### Claim 15

A storage device, comprising:
a non-volatile storage unit, wherein a capacity of the non-volatile storage unit is divided into a plurality of streams, and wherein the non-volatile storage unit comprises a plurality of dies, each of the plurality of dies comprising a plurality of planes, each of the planes comprising a plurality of erase blocks, and each of the erase blocks comprising a plurality of wordlines; and
means for receiving commands to write data received from a host device in a minimum write size, wherein the minimum write size is set by multiplying a number of erase blocks in a stream dedicated to storing user data times a pages per cell of the wordlines times a wordline size, and subtracting an amount of space dedicated to storing metadata of the storage device.

### Claim 16 (depends on 15)

The storage device of claim 15, wherein the minimum write size is set to align to a size of a wordline.

### Claim 17 (depends on 15)

The storage device of claim 15, wherein the minimum write size is a factory setting of the storage device.

### Claim 18 (depends on 15)

The storage device of claim 15, wherein one or more streams individually comprises 32 dies, and wherein at least 30 dies of the 32 dies of each of the one or more streams are dedicated to storing user data.

### Claim 19 (depends on 18)

The storage device of claim 18, wherein at least one die of the 32 dies of each of the one or more streams is dedicated to storing parity data.

### Claim 20 (depends on 18)

The storage device of claim 18, wherein a first die of the 32 dies of each of the one or more streams is dedicated to storing p-parity data and a second die of the 32 dies of each of the one or more streams is dedicated to storing q-parity data.