Maybe my explanation was a little bit incorrect. I mean outbound socket usage. So FS fires events to Event Socket Server.
After your remark i checked again wiki, and found (https://wiki.freeswitch.org/wiki/Event_Socket_Outbound#Events): 

By default, the connected socket will not receive any freeswitch events. You can issues following event commands to let freeswitch send events the connected socket.

Receive only events from this channel. 

Similar reasoning, filtering could be done similar as for inbound socket, or it general behavior for inbound\outbound sockets.

On Thu, Jun 11, 2015 at 7:59 PM, Michael Jerris <mike@jerris.com> wrote:
To the contrary, the link you responded to includes information on how to do that filtering on FreeSWITCH by subscribing to only the events you want 


On Thursday, June 11, 2015, Vlad Fabi <vaad.fabi@gmail.com> wrote:
actually FreeSWITCH implements a fairly good filtering on its ESL interface:
https://freeswitch.org/confluence/display/FREESWITCH/mod_event_socket
You can subscribe to events of specific types and/or only for specific channels

But as i can see, there is no information and possibility to filter events on FS side before sending to Event Socket Server.  On remote side (Event Socket Server) - no problem, just receive all events, filter it and process only you need.
As a result - too much events, highload and FS call processing problems as wrote earlier Kamil ...

On Thu, Jun 11, 2015 at 5:27 PM, Stanislav Sinyagin <ssinyagin@gmail.com> wrote:
actually FreeSWITCH implements a fairly good filtering on its ESL interface:
https://freeswitch.org/confluence/display/FREESWITCH/mod_event_socket

You can subscribe to events of specific types and/or only for specific channels

On Thu, Jun 11, 2015 at 4:20 PM, Vlad Fabi <vaad.fabi@gmail.com> wrote:
>> probably you subscribed to all events, and that's why you get so much
>> traffic on ESL connection? usually you need only specific events on
>> specific channels
>
> So, this mean there is chance that Event Socket Server (if event filters
> activated) works properly under highload (more than 50cps\300channels).
> But after Kamil message, i falled in doubts...
> As i understand, all events fires from FS to Event Socket Server, to
> minimize sending events (load) we need to filter it on FS side. In this case
> this FS send to Event Socket Server only required events. But i am not sure
> FS can filter it on it's side.
> Second case - combine scripts handlers\curl modules with minimal events to
> Event Socket Server. This way is more complicated, but higload hopefull.
>
> Kamil, you brought uncertainty into my thoughts! :))
>
>
> On Thu, Jun 11, 2015 at 1:38 PM, Stanislav Sinyagin <ssinyagin@gmail.com>
> wrote:
>>
>> probably you subscribed to all events, and that's why you get so much
>> traffic on ESL connection? usually you need only specific events on
>> specific channels
>>
>> On Thu, Jun 11, 2015 at 12:33 PM, Kamil Nigmatullin
>> <kamil.nigmatullin@gmail.com> wrote:
>> >> In my view, and with my experiance it is not a good idea to be
>> >> connected
>> >> to FS all time.
>> >
>> > Why? For whole call life control is good approach, because external
>> > application know all information about call state and events.  Or all
>> > events
>> > external application, that receives and fires events to FS  - this is my
>> > way.
>> >
>> > I thought this way as well. But when I tried to make stress test for
>> > 50cps
>> > 300 concurrent, I had some unclosed calls. So then I moved almost  code
>> > to
>> > LUA. And only some commands like originate or reschedules of hangup left
>> > on
>> > ESL. And I was afraid by how traffic between FS and external program is
>> > huge.
>> >
>> >> Better to use one time connection to execute some commands.
>> >
>> > Hmm, this takes extra overhead for creation\closing connections. By the
>> > way,
>> > for outbound socket connection FS use persistent connection or per event
>> > connection ?
>> > I thing this overhead is nothing comparing to all events that FS sends
>> > to
>> > your external program.
>> >
>> > By the way, for outbound socket connection FS use persistent connection
>> > or
>> > per event connection ?
>> > It is not by Event. In Inbound Socket I think it is the only connection
>> > you
>> > have for all calls and events.
>> >
>> >
>> >
>> > --
>> > Kamil Nigmatullin
>> > Tel: 77272323748
>> > mob: 7 (707) 2517003
>> > Skype: kamil.nigmatullin
>> >
>> >
>> > _________________________________________________________________________
>> > Professional FreeSWITCH Consulting Services:
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>> > http://www.freeswitchsolutions.com
>> >
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>> > http://www.cluecon.com
>> >
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>>
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>
>
> _________________________________________________________________________
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>
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>
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_________________________________________________________________________
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_________________________________________________________________________
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