nfssrv:rfs_write_async
Parameter
- Description
-
Controls the behavior of the NFS version 2 server when it processes
WRITE
requests. The NFS version 2 protocol mandates that all modified data and metadata associated with theWRITE
request reside on stable storage before the server can respond to the client. NFS version 2WRITE
requests are limited to 8192 bytes of data. Thus, eachWRITE
request might cause multiple small writes to the storage subsystem. This can cause a performance problem.One method to accelerate NFS version 2
WRITE
requests is to take advantage of a client behavior. Clients tend to sendWRITE
requests in batches. The server can take advantage of this behavior by clustering together the differentWRITE
requests into a single request to the underlying file system. Thus, the data to be written to the storage subsystem can be written in fewer, larger requests. This method can significantly increase the throughput forWRITE
requests. - Data Type
-
Integer (32-bit)
- Default
-
1 (clustering enabled)
- Range
-
0 (clustering disabled) or 1 (clustering enabled)
- Units
-
Boolean values
- Dynamic?
-
Yes
- Validation
-
None
- When to Change
-
Some very small NFS clients, particularly PC clients, might not batch
WRITE
requests. Thus, the behavior required from the clients might not exist. In addition, the clustering in the NFS version 2 server might just add overhead and slow down performance instead of increasing it. - Commitment Level
-
Unstable