Thread: exponential performance decrease, problem with version postgres + RHEL?
Hello everybody,
We have being doing some testing with an ISD transaction and we had
some problems that we posted here.
The answers we got were very kind and useful but we couldn't solve the problem.
We have doing some investigations after this and we are thinking if is
it possible that OS has something to do with this issue. I mean, we
have two hosts, both of them with OS = Red Hat Enterprise Linux Server
release 6.2 (Santiago)
But when doing "select * from version()" on the postgres shell we obtain:
sessions=# select * from version();
version
--------------------------------------------------------------------------------------------------------------
PostgreSQL 9.1.3 on x86_64-unknown-linux-gnu, compiled by gcc (GCC)
4.4.6 20110731 (Red Hat 4.4.6-3), 64-bit
(1 row)
We don't understand why in here it's written "(Red Hat 4.4.6-3)".
Is it possible that we have installed a postgres' version that it's
not perfect for the OS?
But if this is a problem, why are we obtaining a normal perform on a
host and an exponential performance decrease on another?
And how can we obtain a normal performance when launching the program
which does the queries from another host (remote url) but when
launching it in the same host we obtain this decrease on the
performance?
Any idea would be great!
Thanks very much!!!!
Useful data:
name |
current_setting
--------------------------+--------------------------------------------------------------------------------------------
------------------
version | PostgreSQL 9.1.3 on
x86_64-unknown-linux-gnu, compiled by gcc (GCC) 4.4.6 20110731 (Red
Hat
4.4.6-3), 64-bit
archive_mode | off
client_encoding | UTF8
fsync | on
lc_collate | en_US.UTF-8
lc_ctype | en_US.UTF-8
listen_addresses | *
log_directory | pg_log
log_filename | postgresql-%a.log
log_rotation_age | 1d
log_rotation_size | 0
log_truncate_on_rotation | on
logging_collector | on
max_connections | 100
max_stack_depth | 2MB
port | 50008
server_encoding | UTF8
shared_buffers | 32MB
synchronous_commit | on
TimeZone | Europe/Madrid
wal_buffers | 64kB
wal_sync_method | fsync
(22 rows)
Re: [PERFORM] exponential performance decrease, problem with version postgres + RHEL?
From
Nikolay Ulyanitsky
Date:
Hi On 28 September 2012 13:43, John Nash <postgres.dba.needs.help@gmail.com> wrote: > We don't understand why in here it's written "(Red Hat 4.4.6-3)". GCC version is 4.4.6-3 on RHEL 6.2 :) -- With best regards, Nikolay
RE: [PERFORM] exponential performance decrease, problem with version postgres + RHEL?
From
"Albe Laurenz"
Date:
John Nash wrote: > We have being doing some testing with an ISD transaction and we had > some problems that we posted here. > > The answers we got were very kind and useful but we couldn't solve the problem. Could you refer to the threads so that you don't get the same advice again? > We have doing some investigations after this and we are thinking if is > it possible that OS has something to do with this issue. I mean, we > have two hosts, both of them with OS = Red Hat Enterprise Linux Server > release 6.2 (Santiago) > > But when doing "select * from version()" on the postgres shell we obtain: > > sessions=# select * from version(); > version > ------------------------------------------------------------------------------------------------------ > -------- > PostgreSQL 9.1.3 on x86_64-unknown-linux-gnu, compiled by gcc (GCC) > 4.4.6 20110731 (Red Hat 4.4.6-3), 64-bit > (1 row) > > We don't understand why in here it's written "(Red Hat 4.4.6-3)". > > Is it possible that we have installed a postgres' version that it's > not perfect for the OS? It means that the PostgreSQL you are using was compiled with a compiler that was compiled on RHEL4. Shouldn't be a problem. > But if this is a problem, why are we obtaining a normal perform on a > host and an exponential performance decrease on another? > > And how can we obtain a normal performance when launching the program > which does the queries from another host (remote url) but when > launching it in the same host we obtain this decrease on the > performance? Try to identify the bottleneck. Is it disk I/O, CPU, memory or something else? > name | > current_setting > > --------------------------+--------------------------------------------------------------------------- > ----------------- > ------------------ > version | PostgreSQL 9.1.3 on > x86_64-unknown-linux-gnu, compiled by gcc (GCC) 4.4.6 20110731 (Red > Hat > 4.4.6-3), 64-bit > archive_mode | off > client_encoding | UTF8 > fsync | on > lc_collate | en_US.UTF-8 > lc_ctype | en_US.UTF-8 > listen_addresses | * > log_directory | pg_log > log_filename | postgresql-%a.log > log_rotation_age | 1d > log_rotation_size | 0 > log_truncate_on_rotation | on > logging_collector | on > max_connections | 100 > max_stack_depth | 2MB > port | 50008 > server_encoding | UTF8 > shared_buffers | 32MB Now that sticks out as being pretty small. Try 1/4 of the memory available for the database, but not more than 2 GB. > synchronous_commit | on > TimeZone | Europe/Madrid > wal_buffers | 64kB That's also pretty small. > wal_sync_method | fsync > (22 rows) Yours, Laurenz Albe
Re: [PERFORM] Re: [PERFORM] exponential performance decrease, problem with version postgres + RHEL?
From
John Nash
Date:
Ah ok! Thank you very much! As it's written: compiled by gcc (GCC) 4.4.6 20110731 we thought that was the gcc version and the one written between () was the OS version. So, this is not a problem! Thank you!!!! 2012/9/28 Nikolay Ulyanitsky <lystor@gmail.com>: > Hi > > On 28 September 2012 13:43, John Nash <postgres.dba.needs.help@gmail.com> wrote: > >> We don't understand why in here it's written "(Red Hat 4.4.6-3)". > > GCC version is 4.4.6-3 on RHEL 6.2 :) > > -- > With best regards, > Nikolay > > > -- > Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-performance