configuration reload

[Anatoli Marinov]

What do you exactly mean with "dynamic configuration"?
I cannot find anything about it ...

On 11/25/2012 12:55 PM, Maxim Dounin wrote:
> Hello!
>
> On Fri, Nov 23, 2012 at 05:53:53PM +0200, Anatoli Marinov wrote:
>
>> *Hello colleagues,
>> We have some troubles when nginx have to reload its configuration.
>> *There is a*control panel and every user which has account may
>> change its own settings. For example it may add new domain name or
>> change other option. After that new config files are created and
>> they are sent to the servers.
>> When there is a new config file master process receives HUP signal
>> and it loads this new configuration. After the configuration is
>> loaded the master process starts new workers and waits for old
>> workers to complete its responses with the end users.  Usually there
>> are several slow connections and old workers can stay alive for a
>> long time.
>> If there are several new configs for small period of time the number
>> of workers may become very high and servers' load also gets high
>> values. In general this is not good for the service.
> That's why it's generally not recommended to do automated
> configuration reloads.  If you do automated reloads - you have to
> implement some safeguards to prevent situation of too many worker
> processes shutting down by either preventing further reloads till
> some workers exit, or killing oldest shutting down workers if
> another reload is strictly required.
>
>> Do you have any idea how this issue could be solved? Is there
>> different way to set new config file without a proc*ess *of new
>> workers creation?
> Current nginx configuration reload code uses new worker processes
> to apply new configuration.  Reimplementing this with some other
> mechanism is certainly possible, but wouldn't be trivial (and I
> suspect might result in other problems).  I would recommend you to
> focus on dynamic configuration of aspects you want to be
> user-configurable without changing main nginx configuration.
>