Re: Too many references: cannot splice

2 Dec 2016


      Sebastian,
On October 13th I sent a new email with subject "Too many references:
cannot splice" with a reference to a lklm post.
You will find more info. and a patch there. I can confirm the patch is
working for us.
Regards,
Luis Ugalde
On Fri, Dec 2, 2016 at 5:23 PM, Sebastian Köhler sk@tyrion.de wrote:
...
Hello,
multiple times per day one of our Dovecot servers has the problem that it
suddenly refuses to accept new connections and then floods the logs with
these messages:
Dec  2 12:43:06 alfa3201 dovecot: pop3-login: Error: fd_send(pop3, 18)
failed: Too many references: cannot splice
Dec  2 12:43:07 alfa3201 dovecot: pop3-login: Error: fd_send(pop3, 18)
failed: Too many references: cannot splice
Dec  2 12:43:07 alfa3201 dovecot: imap-login: Error: fd_send(imap, 16)
failed: Too many references: cannot splice
Dec  2 12:43:07 alfa3201 dovecot: imap-login: Error: fd_send(imap, 16)
failed: Too many references: cannot splice
We have to either do a restart of the server or a doveadm kick on all
users to make it reachable again. On my search for a solution I found a
similar report from March[1] however without a fix.
[1] http://dovecot.org/pipermail/dovecot/2016-March/103514.html
dovecot -n
# 2.2.24 (a82c823): /etc/dovecot/dovecot.conf
# Pigeonhole version 0.4.13 (7b14904)
# OS: Linux 4.4.17-040417-generic x86_64 Debian 8.6
auth_mechanisms = plain login
debug_log_path = /var/log/dovecot-debug.log
default_client_limit = 8003
default_process_limit = 2000
default_vsz_limit = 512 M
disable_plaintext_auth = no
listen = *
login_greeting = [CENSORED] - ready.
mail_location = maildir:~/Maildir:CONTROL=/opt/dovecot/control/%n-
control:INDEX=/opt/dovecot/index/%n
mail_plugins = " stats quota"
namespace inbox {
inbox = yes
location =
mailbox Drafts {
auto = subscribe
special_use = \Drafts
}
mailbox Spam {
auto = subscribe
special_use = \Junk
}
mailbox Sent {
auto = subscribe
special_use = \Sent
}
mailbox "Sent Messages" {
special_use = \Sent
}
mailbox Trash {
auto = subscribe
special_use = \Trash
}
prefix = INBOX.
separator = .
}
passdb {
args = dovecot-%s
driver = pam
}
plugin {
quota = fs:%n(soft quota)
sieve = ~/.dovecot.sieve
sieve_dir = ~/sieve
stats_command_min_time = 1 mins
stats_domain_min_time = 12 hours
stats_ip_min_time = 12 hours
stats_memory_limit = 16 M
stats_refresh = 30 secs
stats_session_min_time = 15 mins
stats_track_cmds = no
stats_user_min_time = 24 hours
}
protocols = " imap pop3"
service auth {
unix_listener /var/spool/postfix/private/auth {
group = postfix
mode = 0666
user = postfix
}
}
service imap-login {
inet_listener imaps {
ssl = yes
}
}
service imap-postlogin {
executable = script-login /etc/dovecot/post-login/expire.sh
}
service imap {
executable = imap imap-postlogin
}
service pop3-login {
inet_listener pop3 {
port = 110
}
inet_listener pop3s {
port = 995
ssl = yes
}
}
service pop3-postlogin {
executable = script-login /etc/dovecot/post-login/expire.sh
}
service pop3 {
executable = pop3 pop3-postlogin
}
service quota-status {
executable = quota-status -p postfix
unix_listener /var/spool/postfix/private/quota {
group = postfix
mode = 0660
user = postfix
}
}
service stats {
fifo_listener stats-mail {
mode = 0666
user = dovecot
}
}
ssl_ca =