======== Required information ====
- iRedMail version: 0.7.3
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MySQL
- Linux/BSD distribution name and version: Debian Squeeze
- Related log if you're reporting an issue:
====

Hi Zhang,

My users have reported excessive delays in webmail, with great delay to login and also display the mailbox.

Did some testing and found that the server was not large load or i/o, but really the webmail was practically unusable.

Found in the log postfix the following:

Dec 10 12:19:47 smtp02 roundcube: IMAP Error: Login failed for xxx@xxx from xx.xxx.66.100. Empty startup greeting (127.0.0.1:143) in /usr/share/apache2/roundcubemail-0.5.4/program/include/rcube_imap.php on line 192 (GET /_task=mail&_remote=1&_action=check-recent&_t=1418221182906&_mbox=INBOX&_list=1&_quota=1&_=1418221182906&_
unlock=0)
Dec 10 12:14:58 smtp02 roundcube: IMAP Error: Login failed for yyy@yyy from yyy.yyy.7.173. Empty startup greeting (127.0.0.1:143) in /usr/share/apache2/roundcubemail-0.5.4/program/include/rcube_imap.php on line 192 (GET /_task=mail&_remote=1&_action=check-recent&_t=1418220831677&_mbox=INBOX&_list=1&_quota=1&_=1418220831677&_unlock=0)

To resolve I restarted Dovecot and also Apache and immediately normalized (quick login and view folders). But after a few minutes again slowed.

Searching in the log dovect found:

Dec 10 11:08:44 dovecot: Warning: All login processes are in use. You may need to increase login_max_processes_count
Dec 10 11:13:56 dovecot: Warning: All login processes are in use. You may need to increase login_max_processes_count
Dec 10 11:18:57 dovecot: Warning: All login processes are in use. You may need to increase login_max_processes_count

Checked system settings and also the Dovecot:

root:~# ulimit -n
2048

root:~# cat /proc/sys/fs/inotify/max_user_instances
128

root:~# dovecot -a |grep max
login_max_processes_count: 128
login_max_connections: 256
max_mail_processes: 512
mail_max_userip_connections: 10
mail_max_keyword_length: 50
mail_log_max_lines_per_sec: 10
imap_max_line_length: 65536

I don´t  know why that, because until then there was this problem.

Can help me solve this?

Tks,

M Martinatti