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
