Re: [PERFORM] DELETE vs TRUNCATE explanation

On Mon, Jul 16, 2012 at 3:18 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Robert Haas <robertmhaas(at)gmail(dot)com> writes:
>> At any rate, I'm somewhat less convinced that the split was a good
>> idea than I was when we did it, mostly because we haven't really gone
>> anywhere with it subsequently.
>
> BTW, while we are on the subject: hasn't this split completely broken
> the statistics about backend-initiated writes?

Yes, it seems to have done just that. The comment for
ForwardFsyncRequest is a few bricks short of a load too:

* Whenever a backend is compelled to write directly to a relation
* (which should be seldom, if the checkpointer is getting its job done),
* the backend calls this routine to pass over knowledge that the relation
* is dirty and must be fsync'd before next checkpoint. We also use this
* opportunity to count such writes for statistical purposes.

Line 2 seems to have been mechanically changed from "background
writer" to "checkpointer", but of course it should still say
"background writer" in this case.

--
Robert Haas
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