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| author | Bryan Schumaker <bjschuma@netapp.com> | 2010-10-21 16:33:18 -0400 |
|---|---|---|
| committer | Trond Myklebust <Trond.Myklebust@netapp.com> | 2010-10-23 15:27:37 -0400 |
| commit | 82f2e5472e2304e531c2fa85e457f4a71070044e (patch) | |
| tree | 45e170b0ec64bcc07e51ae36919ca6cba1163703 /fs/nfs/client.c | |
| parent | ae42c70a60fe330d9c2af7c4b92ce78484308e37 (diff) | |
| download | lwn-82f2e5472e2304e531c2fa85e457f4a71070044e.tar.gz lwn-82f2e5472e2304e531c2fa85e457f4a71070044e.zip | |
NFS: Readdir plus in v4
By requsting more attributes during a readdir, we can mimic the readdir plus
operation that was in NFSv3.
To test, I ran the command `ls -lU --color=none` on directories with various
numbers of files. Without readdir plus, I see this:
n files | 100 | 1,000 | 10,000 | 100,000 | 1,000,000
--------+-----------+-----------+-----------+-----------+----------
real | 0m00.153s | 0m00.589s | 0m05.601s | 0m56.691s | 9m59.128s
user | 0m00.007s | 0m00.007s | 0m00.077s | 0m00.703s | 0m06.800s
sys | 0m00.010s | 0m00.070s | 0m00.633s | 0m06.423s | 1m10.005s
access | 3 | 1 | 1 | 4 | 31
getattr | 2 | 1 | 1 | 1 | 1
lookup | 104 | 1,003 | 10,003 | 100,003 | 1,000,003
readdir | 2 | 16 | 158 | 1,575 | 15,749
total | 111 | 1,021 | 10,163 | 101,583 | 1,015,784
With readdir plus enabled, I see this:
n files | 100 | 1,000 | 10,000 | 100,000 | 1,000,000
--------+-----------+-----------+-----------+-----------+----------
real | 0m00.115s | 0m00.206s | 0m01.079s | 0m12.521s | 2m07.528s
user | 0m00.003s | 0m00.003s | 0m00.040s | 0m00.290s | 0m03.296s
sys | 0m00.007s | 0m00.020s | 0m00.120s | 0m01.357s | 0m17.556s
access | 3 | 1 | 1 | 1 | 7
getattr | 2 | 1 | 1 | 1 | 1
lookup | 4 | 3 | 3 | 3 | 3
readdir | 6 | 62 | 630 | 6,300 | 62,993
total | 15 | 67 | 635 | 6,305 | 63,004
Readdir plus disabled has about a 16x increase in the number of rpc calls and
is 4 - 5 times slower on large directories.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Diffstat (limited to 'fs/nfs/client.c')
| -rw-r--r-- | fs/nfs/client.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/fs/nfs/client.c b/fs/nfs/client.c index 876ba8592706..da2f2f024a4d 100644 --- a/fs/nfs/client.c +++ b/fs/nfs/client.c @@ -1358,8 +1358,9 @@ static int nfs4_init_server(struct nfs_server *server, /* Initialise the client representation from the mount data */ server->flags = data->flags; - server->caps |= NFS_CAP_ATOMIC_OPEN|NFS_CAP_CHANGE_ATTR| - NFS_CAP_POSIX_LOCK; + server->caps |= NFS_CAP_ATOMIC_OPEN|NFS_CAP_CHANGE_ATTR|NFS_CAP_POSIX_LOCK; + if (!(data->flags & NFS_MOUNT_NORDIRPLUS)) + server->caps |= NFS_CAP_READDIRPLUS; server->options = data->options; /* Get a client record */ |