Hi,
I try to restore a table on U16.04, but it's ten times slower than on U14.04. This is the definition of the table: testdb=# \d photos_searchlog Table "public.photos_searchlog" Column | Type | Collation | Nullable | Default ----------+--------------------------+-----------+----------+---------------------------------------------- id | integer | | not null | nextval('photos_searchlog_id_seq'::regclass) created | timestamp with time zone | | not null | updated | timestamp with time zone | | not null | lang | character varying(2) | | not null | q | character varying(255) | | not null | hits | integer | | not null | count | integer | | not null | ip_list | text | | not null | locked | boolean | | not null | ts_list | text | | not null | ts_count | integer | | not null | Indexes: "photos_searchlog_pkey" PRIMARY KEY, btree (id) "photos_searchlog_lang_q_key" UNIQUE CONSTRAINT, btree (lang, q) "photos_searchlog_count" btree (count) "photos_searchlog_created" btree (created) "photos_searchlog_ts_count" btree (ts_count) "photos_searchlog_updated" btree (updated) It's only the statement ALTER TABLE ONLY photos_searchlog ADD CONSTRAINT photos_searchlog_lang_q_key UNIQUE (lang, q); which causes the delay. I use the default postgres configuration on the same hardware (/etc/postgresql/10/main/postgresql.conf). I tested different postgres versions, checked the locale and other settings but can not find any differences. I also tried with more or less data, but always the same result. Does anybody have a clue what could cause the time difference? Thanks