On 19/08/2010 12:23, Philippe Rimbault wrote:
On 19/08/2010 11:51, Scott Marlowe wrote:
On Thu, Aug 19, 2010 at 2:07 AM, Philippe Rimbault<primbault@xxxxxx>
wrote:
Hi,
I'm having a strange performance result on a new database server
compared to
my simple desktop.
The configuration of the new server :
- OS : GNU/Linux Debian Etch x86_64
- kernel : Linux 2.6.26-2-vserver-amd64 #1 SMP Sun Jun 20
20:40:33 UTC
2010 x86_64 GNU/Linux
(tests are on the "real server", not on a vserver)
- CPU : 2 x Six-Core AMD Opteron(tm) Processor 2427 @ 2.20GHz
- RAM : 32 Go
The configuration of my desktop pc :
- OS : GNU/Linux Debian Testing i686
- kernel : Linux 2.6.32-5-686 #1 SMP Tue Jun 1 04:59:47 UTC 2010
i686
GNU/Linux
- CPU : Intel(R) Core(TM)2 Duo CPU E7500 @ 2.93GHz
- RAM : 2 Go
PERFORMANCE STUFF DELETED FOR BREVITY
Do you think it's a 32bit/64bit difference ?
No, it's likely that your desktop has much faster CPU cores than your
server, and it has drives that may or may not be obeying fsync
commands. Your server, OTOH, has more cores, so it's likely to do
better under a real load. And assuming it has more disks on a better
controller it will also do better under heavier loads.
So how are the disks setup anyway?
Thanks for your reply !
The server use a HP Smart Array P410 with a Raid 5 array on Sata 133
disk.
My desktop only use one Sata 133 disk.
I was thinking that my simples queries didn't use disk but only memory.
I've launch a new pgbench with much more client and transactions :
Server :
postgres$ pgbench -c 400 -t 100
starting vacuum...end.
transaction type: TPC-B (sort of)
scaling factor: 1
query mode: simple
number of clients: 400
number of transactions per client: 100
number of transactions actually processed: 40000/40000
tps = 115.054386 (including connections establishing)
tps = 115.617186 (excluding connections establishing)
real 5m47.706s
user 0m27.054s
sys 0m59.804s
Desktop :
postgres$ time pgbench -c 400 -t 100
starting vacuum...end.
transaction type: TPC-B (sort of)
scaling factor: 1
query mode: simple
number of clients: 400
number of transactions per client: 100
number of transactions actually processed: 40000/40000
tps = 299.456785 (including connections establishing)
tps = 300.590503 (excluding connections establishing)
real 2m13.604s
user 0m5.304s
sys 0m13.469s
I've re-init the pgbench with -s 400 and now server work (very) better
than desktop.
So ... my desktop cpu is faster if i only work with small query but
server handle better heavier loads.
I was just suprise about the difference on my small database.
Thx
--
Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-performance
