Re: assertion failure 9.3.4

On 04/17/2014 10:15 AM, Andrew Dunstan wrote:
>
> On 04/16/2014 10:28 PM, Tom Lane wrote:
>> Andrew Dunstan <andrew(at)dunslane(dot)net> writes:
>>> On 04/16/2014 07:19 PM, Tom Lane wrote:
>>>> Yeah, it would be real nice to see a self-contained test case for
>>>> this.
>>> Well, that might be hard to put together, but I did try running without
>>> pg_stat_statements and auto_explain loaded and the error did not occur.
>>> Not sure where that gets us in terms of deciding on a culprit.
>> Could we at least see the exact parameter settings for
>> pg_stat_statements
>> and auto_explain? (And any other GUCs with nondefault values?)
>>
>>
>
>
> Here are all the settings from the run that failed:
>
> listen_addresses = '*'
> port = 5432
> fsync = on
> synchronous_commit = off
> checkpoint_segments = 128
> checkpoint_completion_target = 0.9
> shared_buffers = 512MB
> max_connections = 300
> work_mem = 128MB
> maintenance_work_mem = 32MB
> effective_cache_size = 16GB
> effective_io_concurrency = 2
> logging_collector = on
> log_destination = 'stderr'
> log_filename = 'postgresql-%a.log'
> log_rotation_size = 0
> log_truncate_on_rotation = on
> log_line_prefix = '%t [%p] %l: '
> log_connections = on
> log_disconnections = on
> log_statement = 'all'
> track_activity_query_size = 10240
> shared_preload_libraries = 'auto_explain,pg_stat_statements'
>
> As you can see, auto_explain's log_min_duration hasn't been set, so it
> shouldn't be doing anything very much, I should think.

There definitely seems to be something going on involving these two
pre-loaded modules. With both auto_explain and pg_stat_statements
preloaded I can reproduce the error fairly reliably. I have also
reproduced it, but less reliably, with auto_explain alone loaded. I have
not reproduced it with pg_stat_statements alone loaded, but Josh Berkus
has reported that another client has experienced something very similar
(duplicate PK errors on a non-assertion-enabled build) with
pg_stat_statements alone loaded.

cheers

andrew