On 09/12/2016 11:39 AM, Tignor, Tom wrote:
>                  Seems I have an additional data point: the sync test
> always takes longer (> 20 secs) if I include conninfo for all cluster
> nodes instead of just the local node. I had previously thought conninfo
> data was only used when needed. Is this not the case?

What if you do

  sync(id=2);

  wait for event (origin=2, confirmed=5, wait on=2, timeout=30);

  sync(id=2);

  wait for event (origin=2, confirmed=5, wait on=2, timeout=30);
  sync(id=2);

  wait for event (origin=2, confirmed=5, wait on=2, timeout=30);


3 times (or more) in a row, does it still take about the same amount of 
time as 1 sync ?

When slonik starts up it contacts all the nodes it has admin conninfo 
for to get the current state/last event from each node.  Maybe your time 
is spent establishing all those connections over SSL





>
>                  Tom J
>
> *From: *Tom Tignor <ttignor at akamai.com>
> *Date: *Monday, September 12, 2016 at 10:52 AM
> *To: *"slony1-general at lists.slony.info" <slony1-general at lists.slony.info>
> *Subject: *sync performance
>
>                  Hello slony1 community,
>
>                  We’ve recently been testing communication reliability
> between our cluster nodes. Our config is a simple setup with one
> provider producing a modest volume of changes (measured in KB/s)
> consumed by 5 direct subscribers, though these are geographically
> distributed. The test is just a sync event followed by a wait on the
> sync originator. Example:
>
> cluster name = ams_cluster;
>
> node 5 admin
>
>        conninfo='dbname=ams
>
>        host=23.79.242.182
>
>        user=ams_slony
>
>        sslmode=verify-ca
>
>        sslcert=/usr/local/akamai/.ams_certs/complete-ams_slony.crt
>
>        sslkey=/usr/local/akamai/.ams_certs/ams_slony.private_key
>
>        sslrootcert=/usr/local/akamai/etc/ssl_ca/canonical_ca_roots.pem';
>
> node 2 admin conninfo = 'dbname=ams user=ams_slony';
>
> sync(id=2);
>
> wait for event (origin=2, confirmed=5, wait on=2, timeout=30);
>
>                  Tests show the script takes 10-20 secs to run on
> different nodes.
>
>                  Can anyone explain what’s happening internally during
> this time, and why it takes so long? On a healthy, lightly loaded
> system, we might have hoped for a sync response in just a couple
> seconds. Our slon daemons are running with mostly default startup options.
>
>                  Thanks in advance,
>
>                  Tom J
>
>
>
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