[SR-Users] Lost of connection with MySQL?

[Daniel-Constantin Mierla]

On 14/02/2017 14:36, Daniel Tryba wrote:
> On Tue, Feb 14, 2017 at 02:27:59PM +0100, Igor Potjevlesch wrote:
>> Looks to be a good idea.
>> I use MySQL and MyISAM, so I understand that async is supported.
> Async (db_insert_mode=2) is supported with any (acc)backend. With myisam you
> can use delayed inserts (db_insert_mode=1). But without even looking at
> the kamailio implementation I'd guess that 2 is the better choice in the
> hope that the sql operation is entirely done in an other thread, with 1
> there might be the chance that setting up/reusing connections might
> block (since insert delayed is a feature on the mysql server side that
> just returns an OK before any writes to disk).
>
>> How should I dimension the number of async_workers?
> I set it to 2, but for acc and a few async sql_ops calls that should be
> overkill. I have no metrics to make a better assumption on the number of
> worker threads.
>
>
... ahh, forgot to say that even with async query, the insert can still
fail if the db operations take too long, because of the timeout value
set to db_mysql. So if the bottleneck is the mysql server, it doesn't
matter how many async workers you create. I typically start 4, but use
them for more than async sql queries.

Cheers,
Daniel

-- 
Daniel-Constantin Mierla
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