Re: [HACKERS] TODO item

> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> > I am suggesting opening and marking a file descriptor as needing fsync
> > even if I only dirty the buffer and not write it.  I understand another
> > backend may write my buffer and remove it before I commit my
> > transaction.  However, I will be the one to fsync it.  I am also
> > suggesting that such file descriptors never get recycled until
> > transaction commit.
> 
> > Is that wrong?
> 
> I see where you're going, and you could possibly make it work, but
> there are a bunch of problems.  One objection is that kernel FDs
> are a very finite resource on a lot of platforms --- you don't really
> want to tie up one FD for every dirty buffer, and you *certainly*
> don't want to get into a situation where you can't release kernel
> FDs until end of xact.  You might be able to get around that by
> associating the fsync-needed bit with VFDs instead of FDs.

OK, at least I was thinking correctly.  Yes, there are serious drawbacks
that make this pretty hard to implement.  Unless Vadim revives this, we
can drop it.

--  Bruce Momjian                        |  http://www.op.net/~candle pgman@candle.pha.pa.us               |  (610)
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