Re: [HACKERS] TODO item

Tatsuo Ishii <t-ishii@sra.co.jp> writes:
> [ use a global sync instead of fsync ]

> 1. Does sync really wait for the completion of data be written on to
> disk?

Linux is *alone* among Unix platforms in waiting; every other
implementation of sync() returns as soon as the last dirty buffer
is scheduled to be written.

> 2. Are we suffered any performance penalty from sync?

A global sync at the completion of every xact would be disastrous for
the performance of anything else on the system.

> However, in most cases the system is dedicated for only PostgreSQL,

"Most cases"?  Do you have any evidence for that?
        regards, tom lane