ITAGAKI Takahiro <itagaki(dot)takahiro(at)lab(dot)ntt(dot)co(dot)jp> writes:
> Attached is a revised patch. It became very simple, but I worry that
> one magic number (BUFFERS_PER_ABSORB) is still left.
Have you checked that this version of the patch fixes the problem you
saw originally? Does the problem come back if you change
BUFFERS_PER_ABSORB to too large a value? If you can identify a
threshold where the problem reappears in your test case, that would help
us choose the right value to use.
I suspect it'd probably be sufficient to absorb requests every few times
through the fsync loop, too, if you want to experiment with that.
regards, tom lane