Re: PANIC: could not flush dirty data: Operation not permitted power8, Redhat Centos

Hi,

On 2019-04-12 20:04:00 +0200, reiner peterke wrote:
> We build Postgres on Power and x86 With the latest Postgres 11 release (11.2) we get error on
> power8 ppc64le (Redhat and CentOS). No error on SUSE on power8

> 2019-04-09 12:30:10 UTC pid:203 xid:0 ip: LOG: listening on IPv4 address "0.0.0.0", port 5432
> 2019-04-09 12:30:10 UTC pid:203 xid:0 ip: LOG: listening on IPv6 address "::", port 5432
> 2019-04-09 12:30:10 UTC pid:203 xid:0 ip: LOG: listening on Unix socket "/tmp/.s.PGSQL.5432"
> 2019-04-09 12:30:10 UTC pid:204 xid:0 ip: LOG: database system was shut down at 2019-04-09 12:27:09 UTC
> 2019-04-09 12:30:10 UTC pid:203 xid:0 ip: LOG: database system is ready to accept connections
> 2019-04-09 12:31:46 UTC pid:203 xid:0 ip: LOG: received SIGHUP, reloading configuration files
> 2019-04-09 12:35:10 UTC pid:205 xid:0 ip: PANIC: could not flush dirty data: Operation not permitted
> 2019-04-09 12:35:10 UTC pid:203 xid:0 ip: LOG: checkpointer process (PID 205) was terminated by signal 6: Aborted

Any chance you can strace this? Because I don't understand how you'd get
a permission error here.

> I get the feeling this is related to the fsync() issue.
> why is it happening on Power RH and CentOS, but not on the other platforms?

Yea, the PANIC is due to various OSs, including linux, basically feeling
free to discard any diryt data after any integrity related calls fail
(we could narrow it down, but it's hard, given the variability between
versions). That is, if they signal such issues at all :(

Greetings,

Andres Freund