Thanks, I absolutely agree that this documentation needs to explain properly how the bgwriter works. Your latest patch looks good, it significantly improves this section of the manual. I would just suggest changing "non-dirty" to "clean" in "When the number of non-dirty shared buffers appears to be insufficient", as this makes the language simpler and avoids introducing another new term (non-dirty, which means the same as clean).
Thanks again, Chris.
On Thu, 12 Nov 2020 at 16:54, Bruce Momjian <bruce@momjian.us> wrote:
On Thu, Nov 12, 2020 at 02:40:04PM +0000, Chris Wilson wrote: > Hi Bruce, > > Thanks, yes I agree that that is much clearer. However when you say: > > > When the percentage of dirty shared buffers is high, the background writer > writes some of them to the file system... > > > I haven't seen anything about a minimum percentage before the bgwriter kicks > in, is that really the case? How is it configured?
Yes, I see your point. My language was not accurate, and it didn't match the actual background writer tuning parameters below this text. Here is an updated doc patch.
I agree this text should be as clear as possible because there is no way to properly tune the background writer parameters unless we explain how it works. It is good you noticed this.
