M Harris wrote:
but ordering of packets over the network isn't a problem. And yes, either TCP or UDP can be used. Thanks. You can tell how long its been since I even tried it... back not many years ago only udp worked. tcp will keep the packets ordered. And
On Wednesday 19 December 2007 09:44, Dave Howorth wrote: thanks for the link.
UDP is stateless (no connection needed) -- but it is a reliable transport for NFS since NFS keeps track of the packet ordering and the packets which are 'outstanding'. TCP is preferred and is the default when it is available. Where TCP gets important is when NFS run between two machines on a *high* speed network (1G or greater). The reason being is that NFS uses a 16-bit counter to order packets. On a high speed network, it's possible too many packets (>65535) can be sent' out in a short time and NFS can get 'confused' and lose a bunch of packets. This is why "tcp" is the default and preferred transport. TCP is available with versions 3 & 4 of NFS (both supported by most modern kernels). A big change in 10.3 (I think), is that 10.3 appears to prefer NFS4 if available over NFS3. NFS "sessions" will use the maximum supported. However, regarding this:
Perhaps things would improve using "async", that's a difference with local filesystems that run "async" by default. But the man page says it can be dangerous.
VERY!
It depends on the environment, but in a local area network, "async" is usually preferred. "Async" causes *great* speed increases when used with NFS that cannot be attained with a 'synchronous' mount. Few 'end users' need 'sync' on NFS mounts. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org