dovecot - Sep 2013 - "service_count = 0" for "service dict" (High-performance mode)

Hi,

I'm running dovecot 2.1.17 with "Login processes" in
"High-performance
mode" as explained here:

service imap-login {
   service_count = 1

http://wiki2.dovecot.org/LoginProcess

but i thinks I should also set "service dict" in high-performance mode
since sometimes the number of dict processes reach the limit of 100 
(from default_process_limit=100) and I find these errors in the logs:

Sep 25 15:32:24 imap(info at xxxx), session=<z9N2SDXnIQCy71XC>: Error: 
read(/usr/local/dovecot-2.1/var/run/dovecot/dict) failed: Connection 
reset by peer
Sep 25 15:32:24 imap(service at xxxx), session=<xKxSSDXnwABb/1Ql>: Error: 
read(/usr/local/dovecot-2.1/var/run/dovecot/dict) failed: Connection 
reset by peer

or

Sep 25 15:33:48 imap(info at xxxx), session=<M8FITTXnwABb/CM9>: Warning: 
read(/usr/local/dovecot-2.1/var/run/dovecot/dict): dict lookup took 5 
seconds
Sep 25 15:33:48 imap(editoria at xxxx), session=<3LpHZTTnDgBdJwmm>: 
Warning: read(/usr/local/dovecot-2.1/var/run/dovecot/dict): dict lookup 
took 5 seconds

Do you think will be better set:

service dict {
   service_count = 0

or default_process_limit=200 (instead of 100)

Thanks

-- 
Alessio Cecchi is:
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@ PLUG -> ex-Presidente, adesso senatore a vita, http://www.prato.linux.it

On 25.9.2013, at 17.48, Alessio Cecchi <alessio at skye.it> wrote:
> I'm running dovecot 2.1.17 with "Login processes" in
"High-performance mode" as explained here:
> 
> service imap-login {
>  service_count = 1
> 
> http://wiki2.dovecot.org/LoginProcess
> 
> but i thinks I should also set "service dict" in high-performance
mode since sometimes the number of dict processes reach the limit of 100 (from
default_process_limit=100) and I find these errors in the logs:
> 
> Sep 25 15:32:24 imap(info at xxxx), session=<z9N2SDXnIQCy71XC>:
Error: read(/usr/local/dovecot-2.1/var/run/dovecot/dict) failed: Connection
reset by peer
> Sep 25 15:32:24 imap(service at xxxx), session=<xKxSSDXnwABb/1Ql>:
Error: read(/usr/local/dovecot-2.1/var/run/dovecot/dict) failed: Connection
reset by peer
dict lookups are synchronous. There can never be more than 1 client handled
simultaneously, so it's not a good idea to set dict's client_limit above
1.
> Do you think will be better set:
> 
> service dict {
>  service_count = 0
This is already 0 by default. The limiting factor is the client_limit, which is
1.
> or default_process_limit=200 (instead of 100)
Not necessary either to do such a global change. I'd set:

service dict {
  process_limit = 200 # or more
}