Re: fsync alternatives (was: Re: [HACKERS] TODO item)

> Yes, the way I understand it is that one backend doing the fsync
> will sync the entire file perhaps forcing a sync in the middle of
> a somewhat critical update being done by another instance of the
> backend.

We don't mind that. Until the transaction is marked as complete, they
can fsync anything we want. We just want all stuff modified by a
transaction fsynced before a transaction is marked as completed.

> I'm aware of the performance implications sync writes cause, but
> using fsync after every write seems to cause massive amounts of
> unessesary disk IO that could be avoided with using explicit
> sync descriptors with little increase in complexity considering
> what I understand of the current implementation.

Yes.

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