[Dovecot] Tuning Login processes for High-performance Mode
Hi,
I'm working for tuning a busy cluster of dovecot servers. Heach server as 4 core, 8GB of RAM and provide POP3 and IMAP access to mailbox. OS is Debian 6.0 and dovecot version is 1.2.15.
I am unsure how to set "login_max_processes_count" and "login_max_connections" for reach the best situation when login_process_per_connection is set to no.
I don't know what value to set login_max_processes_count.
For example is better the first or the second configuration?
login_process_per_connection=no login_processes_count=4 login_max_processes_count=8 login_max_connections=512 login_process_size=128
login_process_per_connection=no login_processes_count=4 login_max_processes_count=16 login_max_connections=256 login_process_size=128
Which is a suggested ratio from login_max_processes_count and login_max_connections ?
Other values are correct?
Thanks
Alessio Cecchi is: @ ILS -> http://www.linux.it/~alessice/ on LinkedIn -> http://www.linkedin.com/in/alessice Assistenza Sistemi GNU/Linux -> http://www.cecchi.biz/ @ PLUG -> ex-Presidente, adesso senatore a vita, http://www.prato.linux.it @ LOLUG -> Socio http://www.lolug.net
On 16.12.2011, at 14.06, Alessio Cecchi wrote:
I'm working for tuning a busy cluster of dovecot servers. Heach server as 4 core, 8GB of RAM and provide POP3 and IMAP access to mailbox. OS is Debian 6.0 and dovecot version is 1.2.15.
I am unsure how to set "login_max_processes_count" and "login_max_connections" for reach the best situation when login_process_per_connection is set to no.
They need to be high enough to handle all the concurrent login / SSL connections.
I don't know what value to set login_max_processes_count.
This doesn't matter so much as login_processes_count. In normal operation the login_processes_count should be around 1-2x of the number of CPU cores. There's no reason to create more processes, so the login_max_process_count might as well be the same as login_processes_count. The login_max_connections then just needs to be high enough.
Il 20/12/2011 06:32, Timo Sirainen ha scritto:
On 16.12.2011, at 14.06, Alessio Cecchi wrote:
I'm working for tuning a busy cluster of dovecot servers. Heach server as 4 core, 8GB of RAM and provide POP3 and IMAP access to mailbox. OS is Debian 6.0 and dovecot version is 1.2.15.
I am unsure how to set "login_max_processes_count" and "login_max_connections" for reach the best situation when login_process_per_connection is set to no.
They need to be high enough to handle all the concurrent login / SSL connections.
I don't know what value to set login_max_processes_count.
This doesn't matter so much as login_processes_count. In normal operation the login_processes_count should be around 1-2x of the number of CPU cores. There's no reason to create more processes, so the login_max_process_count might as well be the same as login_processes_count. The login_max_connections then just needs to be high enough.
Thanks Timo,
I had read on wiki the ratio from core and login_processes_count, but I did not understand the ratio from login_processes_count and login_max_processes_count.
So, if I have 4 core and want to serve up to 1024 users, an example of configuration can be:
login_processes_count = 4 login_max_processes_count = 8 login_max_connections = 128
Right?
Alessio Cecchi is: @ ILS -> http://www.linux.it/~alessice/ on LinkedIn -> http://www.linkedin.com/in/alessice Assistenza Sistemi GNU/Linux -> http://www.cecchi.biz/ @ PLUG -> ex-Presidente, adesso senatore a vita, http://www.prato.linux.it @ LOLUG -> Socio http://www.lolug.net
On Tue, 2011-12-20 at 08:24 +0100, Alessio Cecchi wrote:
I had read on wiki the ratio from core and login_processes_count, but I did not understand the ratio from login_processes_count and login_max_processes_count.
Just set login_max_processes_count to same as login_processes_count and you don't have to wonder about it. I don't know if any other values make much sense anyway.
Il 20/12/2011 08:39, Timo Sirainen ha scritto:
On Tue, 2011-12-20 at 08:24 +0100, Alessio Cecchi wrote:
I had read on wiki the ratio from core and login_processes_count, but I did not understand the ratio from login_processes_count and login_max_processes_count.
Just set login_max_processes_count to same as login_processes_count and you don't have to wonder about it. I don't know if any other values make much sense anyway.
Ok, thanks for this suggestion.
Bye
-- Alessio Cecchi is: @ ILS -> http://www.linux.it/~alessice/ on LinkedIn -> http://www.linkedin.com/in/alessice Assistenza Sistemi GNU/Linux -> http://www.cecchi.biz/ @ PLUG -> ex-Presidente, adesso senatore a vita, http://www.prato.linux.it @ LOLUG -> Socio http://www.lolug.net
participants (2)
-
Alessio Cecchi
-
Timo Sirainen