Windows® Internals, Sixth Edition, Part 2

Describes the loader behavior to use when a boot driver has failed to load. Fatal will prevent booting, while UseErrorControl causes the system to honor a driver’s default error behavior, specified in its service key.

ems

Boolean

Instructs the kernel to use EMS as well. (If only bootems is used, only the boot loader will use EMS.)

evstore

String

Stores the location of a boot preloaded hive.

exportascd

Boolean

If this option is set, the kernel will treat the ramdisk file specified as an ISO image and not a Windows Installation Media (WIM) or System Deployment Image (SDI) file.

groupaware

Boolean

Forces the system to use groups other than zero when associating the group seed to new processes. Used only on 64-bit Windows.

groupsize

Integer

Forces the maximum number of logical processors that can be part of a group (maximum of 64). Can be used to force groups to be created on a system that would normally not require them to exist. Must be a power of 2, and is used only on 64-bit Windows.

hal

HAL image name

Overrides the default file name for the HAL image (hal.dll). This option can be useful when booting a combination of a checked HAL and checked kernel (requires specifying the kernel element as well).

halbreakpoint

Boolean

Causes the HAL to stop at a breakpoint early in HAL initialization. The first thing the Windows kernel does when it initializes is to initialize the HAL, so this breakpoint is the earliest one possible (unless boot debugging is used). If the switch is used without the /DEBUG switch, the system will elicit a blue screen with a STOP code of 0x00000078 (PHASE0_ EXCEPTION).

hypervisorbaudrate

Baud rate in bps

If using serial hypervisor debugging, specifies the baud rate to use.

hypervisorchannel

Channel number from 0 to 62

If using FireWire (IEEE 1394) hypervisor debugging, specifies the channel number to use.

hypervisordebug

Boolean

Enables debugging the hypervisor.

hypervisordebugport

COM port number

If using serial hypervisor debugging, specifies the COM port to use.

hypervisordebugtype

Serial, 1394

Specifies which hardware port to use for hypervisor debugging.

hypervisordisableslat

Boolean

Forces the hypervisor to ignore the presence of the Second Layer Address Translation (SLAT) feature if supported by the processor.

hypervisorlaunchtype

Off, Auto

Enables loading of the hypervisor on a Hyper-V system, or forces it to be disabled.

hypervisorpath

Hypervisor binary image name

Specifies the path of the hypervisor binary.

hypervisoruselargevtlb

Boolean

Enables the hypervisor to use a larger amount of virtual TLB entries.

increaseuserva

Size in MB

Increases the size of the user process address space from 2 GB to the specified size, up to 3 GB (and therefore reduces the size of system space). Giving virtual-memory-intensive applications such as database servers a larger address space can improve their performance. (See the section “Address Space Layout” in Chapter 9 for more information.)

kernel

Kernel image name

Overrides the default file name for the kernel image (Ntoskrnl.exe). This option can be useful when booting a combination of a checked HAL and checked kernel (requires specifying the hal element to be used as well).

lastknowngood

Boolean

Boots the last known good configuration, instead of the current control set.

loadoptions

Extra command-line parameters

This option is used to add other command-line parameters that are not defined by BCD elements. These parameters could be used to configure or define the operation of other components on the system that might not be able to use the BCD (such as legacy components).

maxgroup

Boolean

Maximizes the number of processor groups that are created during processor topology configuration. See Chapter 3 in Part 1 for more information about group selection and its relationship to NUMA.

maxproc

Boolean

Forces the maximum number of supported processors that Windows will report to drivers and applications to accommodate the arrival of additional CPUs via dynamic processor support.

msi

Default, ForceDisable

Allows disabling support for message signaled interrupts.

nocrashautoreboot

Boolean

Disables the automatic reboot after a system crash (blue screen).

nointegritychecks

Boolean

Disables integrity checks performed by Windows when loading drivers. Automatically removed at the next reboot.

nolowmem

Boolean