Managing the System Registry Hive on Windows Server 2003 and Windows Server 2008 Integrity Systems

Deciding Whether to Implement a Single ControlSet strategy

Deploying a single ControlSet strategy (described in section, “System Recovery” (page 11)), can

immediately reclaim approximately half the System hive space. You should deploy a single

ControlSet strategy if the HP Registry Monitor Service has posted an Error message to the

Windows System Event Log (similar to Figure 12), as the Hive is nearing its limit. Although this

action will provide an immediate gain in space, it is still important to survey the System hive

afterwards to determine which subkeys are the most costly, and see if they can be reduced. If

the hive continues to grow without bound, it must be actively managed.

If a single ControlSet solution is implemented and the service continues to call out errors then

it becomes mandatory to discover what is responsible for the growth of the hive. If it is impossible

to circumvent this growth through active management, the next step must be to deploy Windows

Server 2008 R2 Itanium Edition, which supports much greater hive sizes.

Optimizing the Hive

Moving to a single ControlSet solution reduces the hive size greatly, yet its disk size remains the

same. This is not optimal for the HP Registry Monitor Service because it has to run a more

in-depth analysis of the hive to determine its true size. It is possible, once the redundant

ControlSet(s) are removed, to compress the System hive down, but this requires a reboot into

WinPE.

In order to reduce the hive's disk size, you must open RegEdit and highlight the System key.

Then export the System hive to a compressed version by using the Export Hive option as shown

in Figure 3 (page 9), making sure to save the file as a hive file.

The System can now be rebooted into WinPE, and the saved hive file can be saved as the new

System hive using the following commands:

rename c:\windows\system32\config\system c:\windows\system32\config\

system.big

c:\windows\system32\config\system.tiny c:\windows\system32\config\system

If the exported System hive is less than 24 MB then the HP Registry Monitor Service does not

need to do an in-depth analysis of the file.

Conclusion

The System hive limit of 32 MB is generally avoidable with care, knowledge, and management

of the contents of the hive ControlSet(s). Specifically, it is imperative to know the size of the

relevant disk keys and whether they have the correct number of entries. With this knowledge,

the Hive can be managed relatively easily, and if configured for a single ControlSet with the

correct number of paths, the system can support very large numbers of disks and partitions.