I have reported this bug earlier of much higher disk writes after upgrading
from Postgres 9.4.3 to 9.4.4. I wanted to check if I should produce any
other details for fixing the issue.
After upgrade from postgres 9.4.3 to 9.4.4 I was seeing constant disk writes
of 4-8MB/s in the background in production. I verified it using iotop and
vmstat. iotop shows "Total Disk Write" to be minuscule (like 10-100Kbps)
but high
"Actual disk writes". It is affecting runtime performance. Postgres
9.4.3 does not have this issue.
It was a continuous disk write even when there was no autovacuum process
running.
It was happening even on a database in which there were no
inserts/deletes/modify
and did vacuum manually.
-Sushant,
