Issue's with socketmap (smmapd) under heavy load?

Andrzej Filip anfi at
Sun Jul 18 02:31:17 EDT 2004

Lenny wrote:
> I did 2 things to try and see if this was ident related. First, I 
> installed an
> identd server on each frontend and backend.
> That had a huge affect on my pop login times, by the way, although I'm 
> unsure
> why (for the better, that is). Unfortunately, once there were at least 100
> sendmails going mail delivery still took over 30 seconds per message.
> The second thing I tried was out of the faq. I added the 
> following
> to my .mc file and remade
>  define(`confTO_IDENT',`0s')dnl
> This doesn't seem to have had any affect either. :( All strace's still show
> waiting for the socketmap socket. Is there any further debugging I could do
> besides an strace that might help point me in the right direction?

Have you checked if your sendmail is compiled with TCPWRAPPERS ?
[ RedHat does it ]
confTO_IDENT controls sendmail ident query, liwrap ident queries are unafected 
by the setting.

BTW you cyrus may hit limit on number of open files desciptors [open files 
(-n) 1024], sendmail keeps one "socket map" session opened per per one active 
SMTP session. Try to increase limit of open file descriptors to 2048 and check 
if it makes the difference.

> Quoting Andrzej Filip <anfi at>:
>> 30s delay make ident query the primary suspect.
>> 1) Take a look at the link below
>> Q3.12 -- Why do connections to the SMTP port take such a long time?
>> 2) Check if you sendmail is compiled with TCPWRAPPERS
>> echo "" | sendmail -bt -d0.1 | grep TCP
>> TCPWRAPPERS uses external library which does its own ident lookups.

Andrzej [en:Andrew] Adam Filip anfi at anfi at
Cyrus Home Page:
Cyrus Wiki/FAQ:
List Archives/Info:

More information about the Info-cyrus mailing list