Horton

Re: pg_basebackup blocking all queries with horrible performance

Lonni J Friedman <netllama@gmail.com>

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From: Lonni J Friedman <netllama@gmail.com>
To: Simon Riggs <simon@2ndquadrant.com>
Cc: Magnus Hagander <magnus@hagander.net>, Fujii Masao <masao.fujii@gmail.com>, Craig Ringer <ringerc@ringerc.id.au>, Jerry Sievers <gsievers19@comcast.net>, pgsql-admin@postgresql.org
Date: 2012-06-20T13:27:17Z
Lists: pgsql-hackers 
On Wed, Jun 20, 2012 at 5:02 AM, Simon Riggs <simon@2ndquadrant.com> wrote:
> On 13 June 2012 02:39, Magnus Hagander <magnus@hagander.net> wrote:
>
>>> I'm running the following, which gets piped over ssh to a remote
>>> server (at gigabit ethernet speed):
>>> pg_basebackup -v -D - -x -Ft -U postgres
>>>
>>> One thing that I've discovered is that if I throttle back the speed of
>>> what is getting piped to the remote server, that directly correlates
>>> to the load on the server.
>>
>> That seems to indicate that you're overloading the I/O system... Or
>> the CPU, but more likely I/O.
>
> CPU utilisation of ssl connections is bad. If network bandwidth is
> good, perhaps running WALSender at full speed with encryption can tank
> the server.

I'm not using SSL.