[mythtv-users] Mysql max-connections and bind-address

[Gary Buhrmaster]

On Fri, Sep 27, 2013 at 12:37 AM, Mark Perkins <perkins1724 at hotmail.com> wrote:
>
>> On 26 Sep 2013, at 7:40 pm, "Simon Hobson" <linux at thehobsons.co.uk> wrote:
....
>> There is a memory requirement per available connection, which according tomysqltuner is currently 4.6M for my setup. That means 100 connections would eat up getting on for half a gig of ram on top of your global memory useage.
>
> [Mark] If I read my output correctly I have 48.7M per thread so multiply your figure by 10 would be somewhere north of 5G. If I recall correctly I have 2G RAM and 2G swap partition so I guess I have a problem there already. Although the database is on a SSD so that probably explains why I don't see any performance impacts (up until when the SSD fails from excessive reads / writes maybe?)

Note that the output from mysqltuner is a "worst case maximum"
(basically, all the connections are actively issuing requests, all
are using join buffers, all are using sort buffers, etc.).  Your actual
use will vary (and for dedicated (for MythTV) MySQL engine, and
for the MythTV case, where most connections are more "idle" than
"active", your actual use will be far less).

There are some specific advice for MySQL tuning on the MythTV
wiki pages at: http://www.mythtv.org/wiki/Tune_MySQL but note
that some of the advice may not apply to your particular usage
(as with much else, MySQL tuning is well understood only by
those that well understand it; for others, it is closer to magic).

Gary