XP下开启4G内存的方法+RAMDISK使用方法

1. Parameters registry is HKLM\System\CurrentControlSet\Services\RRamdisk\Parameters\ why RRamdisk, 'cause XP SP1 contain a Ramdisk driver for XP Embeded. 2. Parameter: DiskSizeM, DiskSizeK your desired disk size, the unit is M bytes or K bytes. The DiskSizeK has higher priority. 3. Parameter: MediaType the reported drive type, 1 -- RAM Drive 2 -- Fixed Media (default) 3 -- Removable Media 4 -- Floppy Diskette 4. Parameter: DriveLetter name say it is, default is R: 5. Parameter: SectorsPerCluster your desired cluster size, zero for driver pickup: <= 2M FAT12, cluster=512 <= 32M FAT16, cluster=512 <= 64M FAT16, cluster=1k <= 128M FAT16, cluster=2k <= 256M FAT16, cluster=4k <= 512M FAT32, cluster=2k <= 16G FAT32, cluster=4k ...... you can specify smaller cluster size, force pre-format as FAT32 6. Parameter: Image maintained by rdutil utlilty, mainly for preload NTFS image. eg: 1) load ramdisk, don't write anything 2) format the ramdisk FORMAT /FS:NTFS /Q /V:RamDisk /A:512 R: 3) adjust logfile to minimum size CHKDSK /L:2048 R: 4) reset access rights CACLS R:\ /G: BUILTIN\Adminstrators:F 5) create necessary structure MKDIR R:\TEMP 6) pack the disk image and save to registry rdutil R: registry Notes: 1) You should leave RamDisk as clean as possible before packing, the max packed image size is 64K. 2) The disk image only valid to same RamDisk size, you should re-create disk image when size changed. 3) The driver internal formater will disable if this registry present, corrupt/size-mismatch value leave an un-formated disk. rdutil utlility usage: 1) backup registry image rdutil save filename 2) restore registry image rdutil load filename 3) report packed image size rdutil R: rdutil registry rdutil unpacked_file second command reading DriveLetter from registry the third is packing an unpacked image file 4) packing image & save to registry rdutil R: registry 5) packing image & save to file rdutil R: packed_file 6) unpacking image rdutil unpack packed_file unpacked_file 7) link NTFS junction to Ramdisk rdutil link temp \ 7. Re-Format RamDisk You can re-format RamDisk except RAMDrive media type. eg: FixedMedia type FORMAT /FS:NTFS /FORCE /Q /V:RamDisk /A:512 R: RemovableMedia type ECHO Y | FORMAT /FS:NTFS /FORCE /Q /V:RamDisk /A:512 R: you can place your format command to startup script. I don't recommend re-format to FAT, the pre-formated RamDisk is more efficient than other format utililty. 8. pagefile support you can set pagefile to FixMedia type disk w/ pre-formated system. if you need other MediaType or re-format, use the addswap.exe utility: addswap r:\pagefile.sys 16 32 create pagefile r:\pagefile.sys with min=16M max=32M. 9. TEMP directory you should set TEMP/TMP directory to TEMP sub-directory, don't use the root directory. 10. NTFS junction point to RAMDrive You can't create NTFS junction point to RAMDrive media type, Fixed & Removable Media type should work 11. Connectix VirtualPC compatibility someone report problem with VirtualPC+physical volume/disk. please set MediaType to RAMDrive/Removable. 12. Mountpoint without DriveLetter Clear DriveLetter registry value will not create Drive Letter for Ramdisk. Attn. Don't delete the DriveLetter registry, which fall to default R:. You can setup mountpoint/junction linking to this unnamed Ramdisk. eg: rdutil link C:\ramdisk link C:\ramdisk to root of Ramdisk rdutil link C:\TEMP TEMP link C:\TEMP to \TEMP at Ramdisk rmdir C:\ramdisk rmdir can remove the link without clear target content NoDriveLetter configuration isn't recommended, because most AntiVirus software cannot realtime scan Volume w/o Drive Letter. ChangeLog: 12.09.2003 fix SMP/HT compatibility 11.26.2003 fix re-format problem & some typo 11.25.2003 merge rdpack and rdj to rdutil 11.24.2003 add DiskSizeK registry, more compatible w/ antivirus software 05.23.2007 x64 support 01.01.2008 support >=4G ram under 32bit windows (UsePAE=1)