The case of PostgreSQL on NFS Server

Hi

This is shikase.
I have a question about PostgreSQL on NFS Server as follows.
Please let me know advice about that. If I posted the wrong mailing-list,
please let me know.

I found the manual 17.2.1 Network File System.

17.2.1 Network File System

If client and server NFS implementations have non-standard
semantics, this can cause reliability problems (see
http://www.time-travellers.org/shane/papers/NFS_considered_harmful.html). Specifically,
delayed
(asynchronous) writes to the NFS server can cause reliability
problems; if possible, mount NFS file systems synchronously
(without caching) to avoid this. Also, soft-mounting NFS is
not recommended.

Particularly, I pay attention the following sentense:
if possible, mount NFS file systems synchronously (without caching)
to avoid this.

In my environment, Database cluster is in NFS server. The instance
of PostgreSQL is working in the one server. not in another server.
I guess that, In my environment, the mount options, system synchronously
and without cache does not need. I means that the sufficient option is
system synchronously only.Because the NFS caching problem might not be
occurred in the case. It also has the good influence about the performance.

But I found it in the manual, So I want to make the following question.

If I mount the database cluster with caching in my environment, What kind of
problem I will meet? Please give the information about the problem you met.

Thank you very much.

Iwao Shikase.
shikase(at)air(dot)co(dot)jp