On Tue, 2003-07-29 at 23:25, Yusuf Goolamabbas wrote:
> In general, MTA's like (qmail/postfix) and their authors assume the
> BSD ffs/softupdates semantics that fsync on a file also syncs the
> directory metadata (I think they want link/rename to be
> synchronous). This semantic is also provided by ext3 in 2 of its modes
> (ordered,data=journal). My question is
>
> a) Does XFS provide similar semantics which would make it reliable as
> a filesystem for MTA queue ?
If you do fsync on a file then the log will get pushed to disk - at
least upto the last transaction involving the inode you do fsync on.
This means that any transaction prior to that (such as a rename or
a link call) is also flushed to disk. So fsync does the right thing.
> b) Are there any mount options which one has to enable this behaviour
> ?
Nope. If you are really paranoid, the wsync mount option makes almost
all transactions synchronous.
>
> Also, what's the version of XFS in the Alan Cox 2.4.22-pre6-ac1 kernel
>
It is somewhat long in the tooth now, and probably has some issues
with the O_DIRECT path.
Steve
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