----- Original Message ----
From: Greg Smith <[EMAIL PROTECTED]>
To: [EMAIL PROTECTED]
Cc: pgsql-general@postgresql.org
Sent: Sunday, February 3, 2008 8:43:28 PM
Subject: Re: [GENERAL] Performance problems with Postgresql/ZFS/Non-global 
zones on Solaris?


On 
Thu, 
31 
Jan 
2008, 
[EMAIL PROTECTED] 
wrote:

> 
I 
haven't 
done 
any 
tuning 
as 
of 
yet. 
I'm 
running 
with 
the 
default 
> 
settings 
produced 
by 
initdb.

The 
default 
settings 
are 
junk 
and 
the 
disk 
pattern 
will 
change 
once 
they're 
set 
correctly, 
so 
tuning 
ZFS 
first 
and 
then 
PostgreSQL 
is 
probably 
backwards.  
You 
may 
return 
to 
tuning 
the 
database 
again 
after 
ZFS, 
but 
for 
the 
first 
shot 
I'd 
start 
with 
a 
somewhat 
tuned 
DB 
server 
and 
then 
play 
with 
the 
filesystem.

Put 
the 
major 
postgresql.conf 
parameters 
in 
the 
right 
ballpark--shared_buffers, 
effective_cache_size, 
and 
a 
large 
setting 
for 
checkpoint_segments 
since 
I 
think 
you 
mentioned 
a 
write-heavy 
benchmark. 
You 
should 
do 
your 
own 
experiments 
with 
wal_sync_method, 
I 
haven't 
seen 
any 
tests 
that 
are 
really 
definitive 
on 
the 
best 
setting 
there 
for 
S10+ZFS 
and 
it 
kind 
of 
depends 
on 
the 
underlying 
hardware--try 
both 
open_datasync 
and 
fdatasync.



Greg,
Thanks for the reply. Unfortunately, the project I'm working is trying to 
provide "database-as-a-service" functionality, so I can't really tune the DB 
since the application/load will vary by customer (and the whole idea was to 
abstract all the low-level tuning parameters from the customer because we 
aren't expecting "power" users). 

Bob

Reply via email to