pg_dump query failed

Hi all,

last week backup of my one database stops with error like below:

"pg_dump: [archiver (db)] query failed: server closed the connection
unexpectedly
This probably means the server terminated abnormally
before or while processing the request.
pg_dump: [archiver (db)] query was: SELECT l.oid, (SELECT rolname FROM
pg_catalog.pg_roles WHERE oid = l.lomowner) AS rolname, (SELECT
pg_catalog.array_agg(acl ORDER BY row_n) FROM (SELECT acl, row_n FROM
pg_catalog.unnest(coalesce(l.lomacl,pg_catalog.acldefault('L',l.lomowner)))
WITH ORDINALITY AS perm(acl,row_n) WHERE NOT EXISTS ( SELECT 1 FROM
pg_catalog.unnest(coalesce(pip.initprivs,pg_catalog.acldefault('L',l.lomowner)))
AS init(init_acl) WHERE acl = init_acl)) as foo) AS lomacl, (SELECT
pg_catalog.array_agg(acl ORDER BY row_n) FROM (SELECT acl, row_n FROM
pg_catalog.unnest(coalesce(pip.initprivs,pg_catalog.acldefault('L',l.lomowner)))
WITH ORDINALITY AS initp(acl,row_n) WHERE NOT EXISTS ( SELECT 1 FROM
pg_catalog.unnest(coalesce(l.lomacl,pg_catalog.acldefault('L',l.lomowner)))
AS permp(orig_acl) WHERE acl = orig_acl)) as foo) AS rlomacl, NULL AS
initlomacl, NULL AS initrlomacl FROM pg_largeobject_metadata l LEFT JOIN
pg_init_privs pip ON (l.oid = pip.objoid AND pip.classoid =
'pg_largeobject'::regclass AND pip.objsubid = 0) "

Additional info:

PostgreSQL 9.6.8 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 4.8.5
20150623 (Red Hat 4.8.5-16), 64-bit

database size 220GB

System CentOS 7

I am not sure how to recognize the problem.

--
Karol Malinowski
Operation Manager
22-118-90-30 | karol(dot)malinowski(at)trustedeyes(dot)pl

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