| From: | Craig Ringer <craig(at)2ndquadrant(dot)com> |
|---|---|
| To: | Andres Freund <andres(at)anarazel(dot)de> |
| Cc: | Thomas Munro <thomas(dot)munro(at)enterprisedb(dot)com>, Simon Riggs <simon(at)2ndquadrant(dot)com>, PostgreSQL Hackers <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: Postgres, fsync, and OSs (specifically linux) |
| Date: | 2018-04-30 05:03:24 |
| Message-ID: | CAMsr+YF=FfuNCcBJXV4tDsxQQ=Yu5GfhZ-z6iiu+Y4x2MYzX0Q@mail.gmail.com |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
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| Lists: | pgsql-hackers |
Hrm, something else that just came up. On 9.6+ we use sync_file_range.
It's surely going to eat errors:
rc = sync_file_range(fd, offset, nbytes,
SYNC_FILE_RANGE_WRITE);
/* don't error out, this is just a performance optimization */
if (rc != 0)
{
ereport(WARNING,
(errcode_for_file_access(),
errmsg("could not flush dirty data: %m")));
}
so that has to panic too.
I'm very suspicious about the safety of the msync() path too.
I'll post an update to my PANIC-everywhere patch that add these cases.
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