Share via


WriteSubrequestLength

Applies To: Windows 8, Windows Server 2012

The WriteSubrequestLength setting works with other settings in the Microsoft-Windows-SecureStartup-FilterDriver component to optimize BitLocker settings for PCs with hardware architectures such as System on a Chip (SoC). Do not use these settings for standard 32-bit or 64-bit hardware architectures.

These settings are intended for OEM manufacturing only. For specific guidance on using these settings, contact Microsoft.

Note

These settings only apply to Windows 8.

Values

WriteSubrequestLength is an integer value, in bytes.

The default value is 524288 (512 MB).

Valid Configuration Passes

offlineServicing

specialize

auditSystem

oobeSystem

Parent Hierarchy

Microsoft-Windows-SecureStartup-FilterDriver | WriteSubrequestLength

Applies To

For a list of the Windows editions and architectures that this component supports, see Microsoft-Windows-SecureStartup-FilterDriver.

XML Example

The following example specifies recommended values for Bitlocker optimizations on an x86 System on a Chip.

<component name="Microsoft-Windows-SecureStartup-FilterDriver" processorArchitecture="x86" publicKeyToken="31bf3856ad364e35" language="neutral" versionScope="nonSxS" xmlns:wcm="https://schemas.microsoft.com/WMIConfig/2002/State" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <BytesDecryptedInDiskRequestOverhead>262144</BytesDecryptedInDiskRequestOverhead>
  <InPlaceCrypto>0</InPlaceCrypto>
  <MaxCryptoRequestsPerIo>4</MaxCryptoRequestsPerIo>
  <MaxDecryptRequests>0</MaxDecryptRequests>
  <MaxEncryptRequests>2</MaxEncryptRequests>
  <ModifiedWriteMaximum>4</ModifiedWriteMaximum>
  <ReadDoubleBuffering>0</ReadDoubleBuffering>
  <SlicedEncryptionInPlace>1</SlicedEncryptionInPlace>
  <SlicedEncryptionMinSize>524288</SlicedEncryptionMinSize>
  <SlicedEncryptionRequestsMax>1</SlicedEncryptionRequestsMax>
  <WriteIoAggregateMaxSize>1048576</WriteIoAggregateMaxSize>
  <WriteIoAggregateMinSize>1048576</WriteIoAggregateMinSize>
  <WriteSubrequestLength>524288</WriteSubrequestLength>
 </component>

See Also

Concepts

Microsoft-Windows-SecureStartup-FilterDriver