For Oracle database and other database engines implemented on UNIX or Linux systems, disabling atime access time updates to filesystems can be an important performance optimization. For Oracle 11gr2 on AIX 7.1, using the noatime mount option for a JFS2 root filesystem should even be considered.
So when I learned about the NtfsDisableLastAccessUpdate registry setting, my first thought was: wow... why did it take so long for me to hear about this?
Now I know :-) I only started paying attention to the Windows Server world after WS2008. Turns out that for WS2008 and beyond, LastAccessTime updates are off by default, as cited below.
http://msdn.microsoft.com/en-us/library/ff469400.aspx
"<16> Section 2.1.1.3: In Windows Vista/Windows Server 2008 and later, LastAccessTime updates are disabled by default in the ReFS and NTFS file systems. It is only updated when the file is closed. This behavior is controlled by the following registry key: HKLM\System\CurrentControlSet\Control\FileSystem\NtfsDisableLastAccessUpdate. A nonzero value means LastAccessTime updates are disabled. A value of zero means they are enabled."
****Updated 3/16/2014****
A registry query for filesystem options will indicate whether LastAccessTime is being maintained or not. A value of 1 for NtfsDisableLastAccessUpdate means its not being maintained - this is default for Windows Server 2008 and beyond. A value of 0 means this access time IS being maintained.
C:\Windows\system32>reg query HKLM\System\CurrentControlSet\Control\FileSystem\
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\FileSystem
DisableDeleteNotification REG_DWORD 0x0
SymlinkLocalToLocalEvaluation REG_DWORD 0x1
SymlinkLocalToRemoteEvaluation REG_DWORD 0x1
SymlinkRemoteToLocalEvaluation REG_DWORD 0x0
SymlinkRemoteToRemoteEvaluation REG_DWORD 0x0
Win31FileSystem REG_DWORD 0x0
Win95TruncatedExtensions REG_DWORD 0x1
NtfsAllowExtendedCharacter8dot3Rename REG_DWORD 0x0
NtfsBugcheckOnCorrupt REG_DWORD 0x0
NtfsDisable8dot3NameCreation REG_DWORD 0x2
NtfsDisableCompression REG_DWORD 0x0
NtfsDisableEncryption REG_DWORD 0x0
NtfsDisableLastAccessUpdate REG_DWORD 0x1
NtfsDisableVolsnapHints REG_DWORD 0x2
NtfsEncryptPagingFile REG_DWORD 0x0
NtfsMemoryUsage REG_DWORD 0x0
NtfsMftZoneReservation REG_DWORD 0x0
NtfsQuotaNotifyRate REG_DWORD 0xe10
UdfsCloseSessionOnEject REG_DWORD 0x3
UdfsSoftwareDefectManagement REG_DWORD 0x0
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\FileSystem
DisableDeleteNotification REG_DWORD 0x0
SymlinkLocalToLocalEvaluation REG_DWORD 0x1
SymlinkLocalToRemoteEvaluation REG_DWORD 0x1
SymlinkRemoteToLocalEvaluation REG_DWORD 0x0
SymlinkRemoteToRemoteEvaluation REG_DWORD 0x0
Win31FileSystem REG_DWORD 0x0
Win95TruncatedExtensions REG_DWORD 0x1
NtfsAllowExtendedCharacter8dot3Rename REG_DWORD 0x0
NtfsBugcheckOnCorrupt REG_DWORD 0x0
NtfsDisable8dot3NameCreation REG_DWORD 0x2
NtfsDisableCompression REG_DWORD 0x0
NtfsDisableEncryption REG_DWORD 0x0
NtfsDisableLastAccessUpdate REG_DWORD 0x1
NtfsDisableVolsnapHints REG_DWORD 0x2
NtfsEncryptPagingFile REG_DWORD 0x0
NtfsMemoryUsage REG_DWORD 0x0
NtfsMftZoneReservation REG_DWORD 0x0
NtfsQuotaNotifyRate REG_DWORD 0xe10
UdfsCloseSessionOnEject REG_DWORD 0x3
UdfsSoftwareDefectManagement REG_DWORD 0x0
****End Updat****
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