Re: pgbench cpu overhead (was Re: lazy vxid locks, v1) - Mailing list pgsql-hackers

From Jeff Janes
Subject Re: pgbench cpu overhead (was Re: lazy vxid locks, v1)
Date
Msg-id BANLkTi=A-TD9qhGjuYDCiav8QfhZwKPsNA@mail.gmail.com
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In response to pgbench cpu overhead (was Re: lazy vxid locks, v1)  (Stefan Kaltenbrunner <stefan@kaltenbrunner.cc>)
Responses Re: pgbench cpu overhead (was Re: lazy vxid locks, v1)
Re: pgbench cpu overhead (was Re: lazy vxid locks, v1)
Re: pgbench cpu overhead (was Re: lazy vxid locks, v1)
Re: pgbench cpu overhead (was Re: lazy vxid locks, v1)
List pgsql-hackers
On Mon, Jun 13, 2011 at 7:03 AM, Stefan Kaltenbrunner
<stefan@kaltenbrunner.cc> wrote:
...
>
>
> so it seems that sysbench is actually significantly less overhead than
> pgbench and the lower throughput at the higher conncurency seems to be
> cause by sysbench being able to stress the backend even more than
> pgbench can.

Hi Stefan,

pgbench sends each query (per connection) and waits for the reply
before sending another.

Do we know whether sysbench does that, or if it just stuffs the
kernel's IPC buffer full of queries without synchronously waiting for
individual replies?

I can't get sysbench to "make" for me, or I'd strace in single client
mode and see what kind of messages are going back and forth.


Cheers,

Jeff


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