Marc Millas <marc.millas@mokadb.com> writes: > I am looking at a postgres 9.6 on rh7 > I see that checkpoint_write_time is huge which looks quite strange as the > average amount of data written is not that big.
checkpoint_write_time is not the amount of time spent doing I/O; it's the elapsed wall-clock time in the write phase. If the I/O is being throttled because of an un-aggressive checkpoint completion target, it could be a lot more than the actual I/O time. What have you got your checkpoint parameters set to?