On Thu, Jun 26, 2014 at 5:49 PM, Mark Kirkwood
<mark.kirkwood@catalyst.net.nz> wrote:
> I have a nice toy to play with: Dell R920 with 60 cores and 1TB ram [1].
>
> The context is the current machine in use by the customer is a 32 core one,
> and due to growth we are looking at something larger (hence 60 cores).
>
> Some initial tests show similar pgbench read only performance to what Robert
> found here
> http://rhaas.blogspot.co.nz/2012/04/did-i-say-32-cores-how-about-64.html
> (actually a bit quicker around 400000 tps).
>
> However doing a mixed read-write workload is getting results the same or
> only marginally quicker than the 32 core machine - particularly at higher
> number of clients (e.g 200 - 500). I have yet to break out the perf toolset,
> but I'm wondering if any folk has compared 32 and 60 (or 64) core read write
> pgbench performance?
My guess is that the read only test is CPU / memory bandwidth limited,
but the mixed test is IO bound.
What's your iostat / vmstat / iotop etc look like when you're doing
both read only and read/write mixed?
