On Thu, May 10, 2012 at 8:34 PM, MauMau wrote:
> Today, they told me that they ran the test on two virtual machines on a
> single physical machine. They also used pgpool-II in both cases. In
> addition, they may have ran the applications and pgpool-II on the same
> virtual machine as the database
From: "Tomas Vondra"
There were some nice talks about performance impact of sync rep, for
example this one:
http://www.2ndquadrant.com/static/2quad/media/pdfs/talks/SyncRepDurability.pdf
There's also a video:
http://www.youtube.com/watch?v=XL7j8hTd6R8
Thanks. The video is especially inter
On Wed, May 9, 2012 at 5:34 PM, MauMau wrote:
> Yes, I understand it is natural for the response time of each transaction to
> double or more. But I think the throughput drop would be amortized among
> multiple simultaneous transactions. So, 50% throughput decrease seems
> unreasonable.
>
> If thi
On 10 Květen 2012, 13:34, MauMau wrote:
> The workload is TPC-C-like write-heavy one; DBT-2. They compared the
> throughput of synchronous replication case against that of no replication
> case.
>
> Today, they told me that they ran the test on two virtual machines on a
> single physical machine. T
MauMau, 10.05.2012 13:34:
Today, they told me that they ran the test on two virtual machines on
a single physical machine.
Which means that both databases shared the same I/O system (harddisks).
Thererfor it's not really surprising that the overall performance goes down if
you increase the I/O
From: "Claudio Freire"
On Wed, May 9, 2012 at 7:34 PM, MauMau wrote:
Yes, I understand it is natural for the response time of each transaction
to
double or more. But I think the throughput drop would be amortized among
multiple simultaneous transactions. So, 50% throughput decrease seems
unrea
On Tue, May 01, 2012 at 04:34:10PM +0200, Clemens Eisserer wrote:
> Quite often Hibernate ends up generating queries with a lot of joins
> which usually works well, except for queries which load some
> additional data based on a previous query (SUBSELECT collections),
> which look like:
>
> select
