[pgpool-general: 5555] Re: pgpool and erlang - request hangs

[Tatsuo Ishii]

Ok, I think I found a another possible cause.  After the client sends
a flush message, it read the socket until Pgpool-II returns a
response. Unfortunately, Pgpool-II keeps on waiting response from
backend, because after "Row description" message returned from backend
because "query in progress" in Pgpool-II is on. Attached patch resets
the flag upon receiving "Row description" message. I hope this solves
your problem.

Best regards,
--
Tatsuo Ishii
SRA OSS, Inc. Japan
English: http://www.sraoss.co.jp/index_en.php
Japanese:http://www.sraoss.co.jp

>> Hello Tatsuo.
>> 
>> Did  you have an opportunity to look into our problem? Is there anything I
>> can do to help you nail this bug?
> 
> I was a little bit busy past 1 week due to attending PGCon in
> Ottawa. I will look into this. BTW, strange thing is, I was succeeded
> in reproducing your problem by using my own test tool and confirmed
> the fix works. Probably there are more causes which I am missing in
> your case.
>>                                         (errmsg("Entered patched location"),
>>                                              errdetail("message type was %c(%02x)", fkind, fkind)));
>>                                         pool_set_doing_extended_query_message();
>>                                 }
>>                                 status = SimpleForwardToBackend(fkind, frontend, backend, len, contents);
>>                                 break;
>>                         }
>> 
>> Indeed, debug log contains records
>>>DEBUG:  Entered patched location
>>>DETAIL:  message type was H(48)
>>>LOCATION:  pool_proto_modules.c:2484
>> 
>> To sum up:
>> replication_mode = off
>> load_balance_mode = on
>> master_slave_mode = on
>> master_slave_sub_mode = 'stream'
>> memory_cache_enabled = off
>> 
>> If master_slave_mode is off, then connection from erlang library does not hang.
> 
> Thank you for additional information.
> 
> Best regards,
> --
> Tatsuo Ishii
> SRA OSS, Inc. Japan
> English: http://www.sraoss.co.jp/index_en.php
> Japanese:http://www.sraoss.co.jp
> _______________________________________________
> pgpool-general mailing list
> pgpool-general at pgpool.net
> http://www.pgpool.net/mailman/listinfo/pgpool-general
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