K 10
svn:author
V 3
jhb
K 8
svn:date
V 27
2012-08-17T14:22:56.841284Z
K 7
svn:log
V 753
MFC 230547:
Add a timeout on positive name cache entries in the NFS client.  That is,
we will only trust a positive name cache entry for a specified amount of
time before falling back to a LOOKUP RPC, even if the ctime for the file
handle matches the cached copy in the name cache entry.  The timeout is
configured via a global 'vfs.nfs.name_timeout' sysctl and defaults to 60
seconds.  It may be set to zero to disable positive name caching entirely.

Note that this can result in increased NFS traffic under certain workloads.
Increasing the threshold can mitigate this somewhat.  Also, to match the
existing 'vfs.nfs.negative_name_timeout' sysctl in 7, this version uses a
sysctl rather than a mount option as in 8.x and later.

Tested by:	Mark Saad

END