[Pdns-dev] virtual memory issue and gmysql

[Patrick Domack]

I did more testing, and actually watched the log file this time and  
the log shows this for every extra 10megs of memory allocated:

Oct  3 00:31:08 blade2 pdns[13541]: Backend error: Failed to execute  
mysql_query, perhaps connection died? Err=1: MySQL server has gone away
Oct  3 00:31:08 blade2 pdns[13541]: gmysql Connection succesful
Oct  3 00:31:08 blade2 pdns[13541]: gmysql Connection succesful
Oct  3 00:31:13 blade2 pdns[13541]: Backend error: Failed to execute  
mysql_query, perhaps connection died? Err=1: MySQL server has gone away
Oct  3 00:31:18 blade2 pdns[13541]: gmysql Connection succesful
Oct  3 00:31:18 blade2 pdns[13541]: gmysql Connection succesful
Oct  3 00:33:18 blade2 pdns[13541]: Backend error: Failed to execute  
mysql_query, perhaps connection died? Err=1: MySQL server has gone away
Oct  3 00:33:18 blade2 pdns[13541]: gmysql Connection succesful
Oct  3 00:33:18 blade2 pdns[13541]: gmysql Connection succesful

This is with a request rate of one every 29 seconds, and a mysql  
timeout of 60 seconds.

This isn't an issue with busy servers, cause it never has a 60sec idle  
time between requests. I don't have this issue with 7 of my production  
server, just the 3 I setup and are in development testing, cause they  
aren't high load yet.
But this means a high load server, that has a temp routing issue or  
other problem, will also start to notice this issue.

Quoting bert hubert <bert.hubert at netherlabs.nl>:

> On Mon, Oct 01, 2007 at 03:30:24AM -0400, Patrick Domack wrote:
>> I have seen reports of this in the users maillist.
>
> Indeed - but quite a number of very large installations do not see a
> problem. So it has to be something site specific.
>
>> the rpm package for pdns-static version 2.9.21
>> on redhat el5 x86_64
>
> Can you count if the chunks of 10240KB it loses correspond to certain errors
> in the log perhaps?
>
> And does your patch fully resolve the issue?
>
> Thanks.
>
>
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