SMTP sessions duration are too long

OS: Windows/Linux; IceWarp Server Version: 11/10

If you have problems with SMTP sessions staying open too long,  hanging your server, then follow those instructions:

Enable mail queue logging via command line
Linux : sh tool.sh modify system C_System_Log_MailQueue 1
Windows : tool.exe modify system C_System_Log_MailQueue 1

It will start logging the processing logs in Icewarp\logs\queue\date.log file. Then you can find out at which stage of processing the session is locked. The logs look like:

SYSTEM [165C] 11:36:48 Message JOO40048 127.0.0.1
SYSTEM [165C] 11:36:48 Size filters end [00]
SYSTEM [165C] 11:36:48 Antivirus begin
SYSTEM [165C] 11:36:51 Antivirus end [00]
SYSTEM [165C] 11:36:51 Antispam begin
SYSTEM [165C] 11:36:51 Antispam end
SYSTEM [165C] 11:36:51 Content filters begin
SYSTEM [165C] 11:36:51 Content filters end [00]
SYSTEM [165C] 11:36:51 Rules begin
SYSTEM [165C] 11:36:51 Rules end [00]
SYSTEM [165C] 11:36:51 Antispam finalization begin
SYSTEM [165C] 11:36:51 Antispam finalization end
SYSTEM [165C] 11:36:51 Delivery
SYSTEM [165C] 11:36:51 Done

Once you see a long-lasting session in Session monitor, just find the thread ID (165C in the example above) and find it in the logs. That way we can troubleshoot where the processing hanged.