Re: found xmin from before relfrozenxid on pg_catalog.pg_authid

On Tue, Mar 20, 2018 at 11:19 AM, Jeremy Finzel <finzelj(at)gmail(dot)com> wrote:

>
>
> On Mon, Mar 19, 2018 at 3:55 PM, Jeremy Finzel <finzelj(at)gmail(dot)com> wrote:
>
>>
>>
>> On Mon, Mar 19, 2018 at 3:53 PM, Peter Geoghegan <pg(at)bowt(dot)ie> wrote:
>>
>>> On Mon, Mar 19, 2018 at 1:01 PM, Jeremy Finzel <finzelj(at)gmail(dot)com>
>>> wrote:
>>> > SELECT heap_page_items(get_raw_page('pg_authid', 7));
>>>
>>> Can you post this?
>>>
>>> SELECT * FROM page_header(get_raw_page('pg_authid', 7));
>>>
>>> --
>>> Peter Geoghegan
>>>
>>
>> @Peter :
>>
>> staging=# SELECT * FROM page_header(get_raw_page('pg_authid', 7));
>> lsn | checksum | flags | lower | upper | special | pagesize |
>> version | prune_xid
>> ----------------+----------+-------+-------+-------+--------
>> -+----------+---------+-----------
>> 262B4/10FDC478 | 0 | 1 | 304 | 2224 | 8192 | 8192
>> | 4 | 0
>> (1 row)
>>
>> @Andres :
>>
>> This is from snapshot (on 9.5.12, but we didn't have the error either on
>> a 9.5.11 snap):
>>
>>
>> heap_page_items
>> ------------------------------------------------------------
>> ------------------------------------------------------------
>> -----------------
>> (1,0,0,0,,,,,,,,,)
>> (2,0,0,0,,,,,,,,,)
>> (3,0,0,0,,,,,,,,,)
>> (4,0,0,0,,,,,,,,,)
>> (5,0,0,0,,,,,,,,,)
>> (6,8080,1,108,3137434815 <(313)%20743-4815>,0,0,
>> "(7,6)",11,10505,32,1111111110000000000000000000000000000000
>> 01111110111100001000010010000001,2166427518 <(216)%20642-7518>)
>> (7,7936,1,144,3137434816 <(313)%20743-4816>,0,0,
>> "(7,7)",11,10507,32,1111111111000000000000000000000000000000
>> 01110111000001110101101100001011,3504005358)
>> (8,0,0,0,,,,,,,,,)
>> (9,0,0,0,,,,,,,,,)
>> (10,7792,1,144,3137434817 <(313)%20743-4817>,0,0
>> ,"(7,10)",11,10507,32,11111111110000000000000000000000000000
>> 0001010110001101000011011111101000,401353834)
>> (11,7680,1,108,3137434818 <(313)%20743-4818>,0,0
>> ,"(7,11)",11,10505,32,11111111100000000000000000000000000000
>> 0001100011010010010001000001100001,2248708806 <(224)%20870-8806>)
>> (12,0,0,0,,,,,,,,,)
>> (13,0,0,0,,,,,,,,,)
>> (14,7568,1,108,3137434819 <(313)%20743-4819>,0,0
>> ,"(7,14)",11,10505,32,11111111100000000000000000000000000000
>> 0001110011110011011011100010100101,2770187214)
>> (15,7456,1,108,3137434820 <(313)%20743-4820>,0,0
>> ,"(7,15)",11,10505,32,11111111100000000000000000000000000000
>> 0011110001010001010011110010100001,2235343503 <(223)%20534-3503>)
>> (16,0,0,0,,,,,,,,,)
>> (17,0,0,0,,,,,,,,,)
>> (18,0,0,0,,,,,,,,,)
>> (19,0,0,0,,,,,,,,,)
>> (20,0,0,0,,,,,,,,,)
>> (21,0,0,0,,,,,,,,,)
>> (22,0,0,0,,,,,,,,,)
>> (23,0,0,0,,,,,,,,,)
>> (24,0,0,0,,,,,,,,,)
>> (25,0,0,0,,,,,,,,,)
>> (26,0,0,0,,,,,,,,,)
>> (27,0,0,0,,,,,,,,,)
>> (28,0,0,0,,,,,,,,,)
>> (29,0,0,0,,,,,,,,,)
>> (30,0,0,0,,,,,,,,,)
>> (31,0,0,0,,,,,,,,,)
>> (32,0,0,0,,,,,,,,,)
>> (33,0,0,0,,,,,,,,,)
>> (34,0,0,0,,,,,,,,,)
>> (35,0,0,0,,,,,,,,,)
>> (36,0,0,0,,,,,,,,,)
>> (37,0,0,0,,,,,,,,,)
>> (38,0,0,0,,,,,,,,,)
>> (39,0,0,0,,,,,,,,,)
>> (40,0,0,0,,,,,,,,,)
>> (41,0,0,0,,,,,,,,,)
>> (42,0,0,0,,,,,,,,,)
>> (43,0,0,0,,,,,,,,,)
>> (44,0,0,0,,,,,,,,,)
>> (45,0,0,0,,,,,,,,,)
>> (46,0,0,0,,,,,,,,,)
>> (47,0,0,0,,,,,,,,,)
>> (48,0,0,0,,,,,,,,,)
>> (49,0,0,0,,,,,,,,,)
>> (50,0,0,0,,,,,,,,,)
>> (51,0,0,0,,,,,,,,,)
>> (52,7344,1,108,3137434821 <(313)%20743-4821>,0,0
>> ,"(7,52)",11,10505,32,11111111100000000000000000000000000000
>> 0011011011111110001010010101000001,2191859675)
>> (53,7232,1,108,3137434822 <(313)%20743-4822>,0,0
>> ,"(7,53)",11,10505,32,11111111100000000000000000000000000000
>> 0001101011010111100110011011100100,661027542)
>> (54,0,0,0,,,,,,,,,)
>> (55,0,0,0,,,,,,,,,)
>> (56,0,0,0,,,,,,,,,)
>> (57,0,0,0,,,,,,,,,)
>> (58,0,0,0,,,,,,,,,)
>> (59,0,0,0,,,,,,,,,)
>> (60,0,0,0,,,,,,,,,)
>> (61,7120,1,108,3137434823 <(313)%20743-4823>,0,0
>> ,"(7,61)",11,10505,32,11111111100000000000000000000000000000
>> 0000010111010110000101010111010100,732568296)
>> (62,6976,1,144,3137434824 <(313)%20743-4824>,0,0
>> ,"(7,62)",11,10507,32,11111111110000000000000000000000000000
>> 0010100100001001001010110000010100,674571301)
>> (63,6864,1,108,3137434825 <(313)%20743-4825>,0,0
>> ,"(7,63)",11,10505,32,11111111100000000000000000000000000000
>> 0010011011011111011100001001010001,2319695577 <(231)%20969-5577>)
>> (64,6720,1,144,3137434826 <(313)%20743-4826>,0,0
>> ,"(7,64)",11,10507,32,11111111110000000000000000000000000000
>> 0001000010011001111011100100101000,345892418)
>> (65,6608,1,108,3137434827 <(313)%20743-4827>,0,0
>> ,"(7,65)",11,10505,32,11111111100000000000000000000000000000
>> 0001000001010100010010101011001010,1398049410)
>> (66,6496,1,108,3137434828 <(313)%20743-4828>,0,0
>> ,"(7,66)",11,10505,32,11111111100000000000000000000000000000
>> 0000101000111100110101001000101010,1414188820)
>> (67,6384,1,108,3137434829 <(313)%20743-4829>,0,0
>> ,"(7,67)",11,10505,32,11111111100000000000000000000000000000
>> 0000110101011101111011001110101001,2513301164 <(251)%20330-1164>)
>> (68,0,0,0,,,,,,,,,)
>> (69,0,0,0,,,,,,,,,)
>> (70,0,0,0,,,,,,,,,)
>> (70 rows)
>>
>>
>> Thanks,
>> Jeremy
>>
>
> Any suggestions as to what I can do from this point? Is it feasible that
> a server restart would fix this, or are you saying it would just mask the
> problem? I can't reproduce it on a snapshot which is quite odd.
>
> FWIW, maybe this is obvious, but the pages look identical on the streamers
> we have to the master.
>
> Thanks,
> Jeremy
>

A server restart and upgrade to 9.5.12 (at the same time), as expected,
made the issue go away. Still doesn't give us any answers as to what
happened or if it would happen again! Thanks for the feeback.

Jeremy