Re: [HACKERS] [PERFORM] pg_dump and thousands of schemas

2012-11-09 Thread Jeff Janes
On Thu, Nov 8, 2012 at 1:04 AM, Denis wrote: > > Still I can't undesrtand why pg_dump has to know about all the tables? Strictly speaking it probably doesn't need to. But it is primarily designed for dumping entire databases, and the efficient way to do that is to read it all into memory in a fe

Re: [PERFORM] Increasing work_mem and shared_buffers on Postgres 9.2 significantly slows down queries

2012-11-09 Thread Andres Freund
On 2012-10-30 14:08:56 -0500, Petr Praus wrote: > select count(*) from contest c > left outer join contestparticipant cp on c.id=cp.contestId > left outer join teammember tm on tm.contestparticipantid=cp.id > left outer join staffmember sm on cp.id=sm.contestparticipantid > left

Re: [PERFORM] Thousands databases or schemas

2012-11-09 Thread Merlin Moncure
On Thu, Nov 8, 2012 at 3:36 AM, Denis wrote: > We have a web application where we create a schema or a database with a > number of tables in it for each customer. Now we have about 2600 clients. > > The problem we met using a separate DB for each client is that the creation > of new DB can take up

Re: [PERFORM] HT on or off for E5-26xx ?

2012-11-09 Thread David Boreham
Here are the SELECT only pgbench test results from my E5-2620 machine, with HT on and off: HT off: bash-4.1$ /usr/pgsql-9.2/bin/pgbench -T 600 -j 48 -c 48 -S starting vacuum...end. transaction type: SELECT only scaling factor: 100 query mode: simple number of clients: 48 number of threads: 48 d