Dovecot impatient with mysql?

[Robert Moskowitz]

On 04/06/2017 12:50 PM, George Kontostanos wrote:
> On Thu, Apr 6, 2017 at 7:10 PM, Robert Moskowitz <rgm at htt-consult.com> wrote:
>> It seems dovecot is impatient with connecting with mysql, as I see in
>> maillog entries like:
>>
>> Apr  6 11:48:30 z9m9z dovecot: dict: Error: mysql(localhost): Connect failed
>> to database (postfix): Can't connect to local MySQL server through socket
>> '/var/lib/mysql/mysql.sock' (13) - waiting for 5 seconds before retry
>> Apr  6 11:48:35 z9m9z dovecot: dict: Error: mysql(localhost): Connect failed
>> to database (postfix): Can't connect to local MySQL server through socket
>> '/var/lib/mysql/mysql.sock' (13) - waiting for 25 seconds before retry
>>
>> I suspect it does connect eventually.  This is a test system with only 1GB
>> of memory and free reports:
>>
>>                total        used        free      shared buff/cache available
>> Mem:        1025484      696344       24556 21528      304584      251552
>> Swap:        524284       92168      432116
>>
>>
>> The production box has 2GB, so if the problem is mysql is swapping out, that
>> will be 'fixed', if it is processor, well this is an ARMv7 duo core, as is
>> the production box.  I am considering buying the new quad core.
>>
>> Is there anything I can do to get dovecot more patient with mysql, or just
>> ignore there messages?
>>
>> thank you
> I really don't understand how you reached to the conclusion that
> dovecot is impatient.

Well, it waits a varying amount of time before reporting the connection 
failed.  Not a fixed amount of time.

Why mysql takes so long to connect via a sock is separate, but I suspect 
it is the low memory and duo core limitations.

Maybe the question is more what is mysql not doing to take so long to 
respond to the connection.