RAM File System Registry Settings (Compact 2013)
3/26/2014
The RAM file system retrieves driver specific settings from the registry. The RAM File system is autoloaded; for more information, see Autoload Settings.
You can add settings for the RAM file system under the registry key HKEY_LOCAL_MACHINE\System\StorageManager\Autoload\ObjectStore.
Enabling Flush-on-Close
If you use the RAM (Object Store) File System, enable flush-on-close registry flushing to make sure that registry changes are flushed every time RegCloseKey is called.
The following registry key shows how to enable flush-on-close:
[HKEY_LOCAL_MACHINE\init\BootVars]
"RegistryFlags"=dword:1
Registry Values
The following table shows registry values that control settings for the RAM File System.
Registry value/Type |
Description |
|---|---|
BootPhase: REG_DWORD |
Set to 0 to load file system before initializing locale. |
DisableFileCompression: REG_DWORD |
Set to 1 to disable file compression. |
Dll: REG_SZ |
Set to "filesys.dll". Specifies the name of the file system DLL. |
LoadFlags: REG_DWORD |
Set to 1 to load file system synchronously |
MountAsBootable: REG_DWORD |
Set to 1 to indicate that the file system contains the system registry. For more information, see Mount Settings. |
MountAsRoot: REG_DWORD |
Mounts the RAM File System as root. Set to 1 only if PRJ_ENABLE_FSMOUNTASROOT sysgen value is not set. Set to 0 to mount the RAM File System as a secondary directory. For more information, see Mount Settings. |
MountPermanent: REG_DWORD |
Set to 1 to indicate this file system can never be dismounted. For more information, see Mount Settings. |
Paging: REG_DWORD |
Set to 1 to enable paging. |
To preserve backward compatibility, mount the Object Store RAM file system as bootable only if PRJ_ENABLE_FSREGHIVE is not set. While mounting as bootable implies that registry hive files are part of the associated file system, hive files are part of the Object Store RAM File System by default.
Similarly, and also to preserve backward compatibility, mount the Object Store RAM file system as the root file system only if PRJ_ENABLE_FSMOUNTASROOT is not set. By default, the Object Store RAM file system is the root file system.
If PRJ_ENABLE_FSREGHIVE and PRJ_ENABLE_FSMOUNTASROOT are not set, and you want to mount the object store as bootable and mount the object store as the root file system, set the following
[HKEY_LOCAL_MACHINE\System\StorageManager\AutoLoad\ObjectStore]
"MountAsBootable"=dword:1
"MountAsRoot"=dword:1
If desired, you can disable file compression for better performance. By default, compression is enabled.
Setting PRJ_DISABLE_RAMFS_COMPRESSION in the build environment before running makeimg will add the necessary key to disable it.
To disable file compression, set the following value:
[HKEY_LOCAL_MACHINE\System\StorageManager\AutoLoad\ObjectStore]
"DisableFileCompression"=dword:1