From karl@denninger.net Sat Oct  20 01:10:38 2012
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Date: Fri, 19 Oct 2012 20:10:24 -0500
From: Karl Denninger <karl@denninger.net>
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Subject: Connection Options -- SSL already uses compression?
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Am I reading this correctly -- it appears that if SSL negotiation is
enabled for a connection (say, when using pg_basebackup over a WAN) that
compression /*is automatically used*/ (provided it is supported on both
ends)?

Is there a way to check and see if it _*is*_ on for a given connection?

I was looking to hack in zlib support and saw that appears to be
already-present support, provided SSL connection security is enabled.

--=20
-- Karl Denninger
/The Market Ticker =AE/ <http://market-ticker.org>
Cuda Systems LLC

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    Am I reading this correctly -- it appears that if SSL negotiation is
    enabled for a connection (say, when using pg_basebackup over a WAN)
    that compression <i><b>is automatically used</b></i> (provided it
    is supported on both ends)?<br>
    <br>
    Is there a way to check and see if it <u><b>is</b></u> on for a
    given connection?<br>
    <br>
    I was looking to hack in zlib support and saw that appears to be
    already-present support, provided SSL connection security is
    enabled.<br>
    <br>
    <div class="moz-signature">-- <br>
      -- Karl Denninger<br>
      <a href="http://market-ticker.org"><i>The Market Ticker &reg;</i></a><br>
      Cuda Systems LLC</div>
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From magnus@hagander.net Sun Oct  21 07:51:10 2012
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Date: Sun, 21 Oct 2012 09:51:03 +0200
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Subject: Re: Connection Options -- SSL already uses compression?
From: Magnus Hagander <magnus@hagander.net>
To: Karl Denninger <karl@denninger.net>
Cc: "pgsql-performance@postgresql.org" <pgsql-performance@postgresql.org>
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On Sat, Oct 20, 2012 at 3:10 AM, Karl Denninger <karl@denninger.net> wrote:
> Am I reading this correctly -- it appears that if SSL negotiation is enabled
> for a connection (say, when using pg_basebackup over a WAN) that compression
> is automatically used (provided it is supported on both ends)?

That would depend on the OpenSSL defaults, I believe. Pretty sure you
can configure that system wide.


> Is there a way to check and see if it is on for a given connection?

You can use PQgetssl() and then use OpenSSL functions to get the info
from there. I'm not sure exactly how, but it would surprise me if it's
not possible.

-- 
 Magnus Hagander
 Me: http://www.hagander.net/
 Work: http://www.redpill-linpro.com/