Re: ERROR: unexpected chunk number 0 (expected 1) for toast value 76753264 in pg_toast_10920100

On 09/06/2017 14:44, Harry Ambrose wrote:
> Hi Tom,
>
> Thanks for attempting to replicate the issue.
>
> Anyway, the bad news is I couldn't reproduce the problem then and I can't
> now. I don't know if it's a timing issue or if there's something critical
> about configuration that I'm not duplicating. Can you explain what sort
> of platform you're testing on, and what nondefault configuration settings
> you're using?
>
>
> Further details about the environment that I can replicate on below:
>
> - Non default postgresql.conf settings:
> checkpoint_segments = 192
> checkpoint_completion_target = 0.9
> checkpoint_timeout = 5min
> wal_keep_segments = 256
> wal_writer_delay = 200ms
> archive_mode = on
> archive_command = 'rsync -e ssh -arv /wal/pg_xlog/%f postgres@<removed hostname>:/wal/pg_xlog'
> archive_timeout = 60
> syslog_facility = 'LOCAL0'
> log_statement = 'mod'
> syslog_ident = 'postgres'
> log_line_prefix = '%h %m %p %c %u %a %e '
> log_timezone = 'GB'
> track_activities = on
> track_counts = on
> datestyle = 'iso, mdy'
> timezone = 'GB'
> default_text_search_config = 'pg_catalog.english'
> array_nulls = on
> sql_inheritance = on
> standard_conforming_strings = on
> synchronize_seqscans = on
> transform_null_equals = off
> - Two node master/slave setup using streaming replication (without slots).
> - CentOS 6.9 (2.6.32-696.el6.x86_64).
> - PostgreSQL 9.4.10 on x86_64-unknown-linux-gnu, compiled by gcc (GCC) 4.4.7 20120313 (Red Hat 4.4.7-17), 64-bit.
> - 64GiB RAM.
> - AMD Opteron(TM) Processor 6238.
> - pg_default sat on 2 disk RAID-1 conifugration (ext3 filesystem).
> - Custom tablespaces (where the errors occur) sat on 4 disk RAID-10 (ext3 filesystem).
> - All disks are HP 600G SAS 6.0Gbps with P420(i) controllers and battery backed cache enabled.
>
Maybe you could give some info on :
- your ext3 mkfs and mount options (journal, barriers, etc)
- your controller setup (battery should be working good and cache mode set to write back)
- your disks setup (write cache should be disabled)
- you should check your syslogs/messages for any errors related to storage
- is your RAM ECC? Did you run any memtest?
- is your CPU overheating ?
- have you experienced any crashes/freezes ?

> Please let me know if you require further info.
>
> Best wishes,
> Harry
>
>

--
Achilleas Mantzios
IT DEV Lead
IT DEPT
Dynacom Tankers Mgmt