Re: TCP network cost

From: Magnus Hagander
Subject: Re: TCP network cost
Date: ,
Msg-id: 49AAD68A.2090308@hagander.net
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In response to: Re: TCP network cost  (Tom Lane)
Responses: Re: TCP network cost  (Linos)
List: pgsql-performance

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TCP network cost  ("Ross J. Reedstrom", )
 Re: TCP network cost  (Rusty Conover, )
  Re: TCP network cost  (, )
  Re: TCP network cost  ("Ross J. Reedstrom", )
   Re: TCP network cost  (Rusty Conover, )
    Re: TCP network cost  ("Ross J. Reedstrom", )
     Re: TCP network cost  ("Ross J. Reedstrom", )
      Re: TCP network cost  (Aaron Turner, )
     Re: TCP network cost  (PFC, )
      Re: TCP network cost  ("Ross J. Reedstrom", )
   Re: TCP network cost  (Gregory Stark, )
    Re: TCP network cost  ("Ross J. Reedstrom", )
     Re: TCP network cost  (Tom Lane, )
      Re: TCP network cost  ("Ross J. Reedstrom", )
       Re: TCP network cost  (Linos, )
        Re: TCP network cost  (Tom Lane, )
         Re: TCP network cost  (Linos, )
          Re: TCP network cost  (Tom Lane, )
           Re: TCP network cost  (Linos, )
            Re: TCP network cost  (Tom Lane, )
             Re: TCP network cost  (Magnus Hagander, )
              Re: TCP network cost  (Linos, )
 Re: TCP network cost  (Aaron Turner, )

Tom Lane wrote:
> Linos <> writes:
>> Tom Lane escribió:
>>> That's just weird --- ssl off should be ssl off no matter which knob you
>>> use to turn it off.  Are you sure it's really off in the slow connections?
>
>> Maybe i am missing something, i use the same command to connect to it
>> from localhost "psql -d database -h localhost" and in the pcap files i
>> have captured the protocol it is clear (with "ssl = false" or "ssl =
>> true" either), but in the debian machine with "ssl = true" in
>> postgresql.conf you can see in the pcap file big time jumps between
>> data packets, psql commandline enables automatically ssl if the server
>> supports it?
>
> Yeah, the default behavior is to do SSL if supported; see PGSSLMODE.
> Non-TCP connections never do SSL, though.  One possibility to check
> is that one of the two distros has altered the default value of
> PGSSLMODE.

IIRC, debian ships with a default certificate for the postgres
installation, so it can actually *use* SSL by default. I don't know if
other distros do that - I think most require you to actually create a
certificate yourself.

//Magnus



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