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<p>I have two servers pointing to an NFS mounted mail spool with
dovecot. Since I recently switched from using Dovecot v1.X, I
have been experiencing high CPU use with the two Dovecot servers.
I am not certain why they are not well behaved. Here is the
configuration information.</p>
<p><br>
</p>
<p>This configuration is currently running at a load average of 17.<br>
</p>
<p>/usr/sbin/dovecot -n<br>
# 2.1.15: /etc/dovecot/dovecot.conf<br>
# OS: Linux 3.10.54-server-2.mga3 i686 Mageia 3<br>
base_dir = /var/run/dovecot/<br>
disable_plaintext_auth = no<br>
lock_method = dotlock<br>
login_greeting = SpamZapper Email ready.<br>
login_log_format_elements = user=<%u> method=%m rip=%r
lip=%l %c<br>
mail_debug = yes<br>
mail_fsync = always<br>
mail_location = maildir:~/Maildir<br>
mail_nfs_index = yes<br>
mail_nfs_storage = yes<br>
mail_privileged_group = mail<br>
mbox_lock_timeout = 15 mins<br>
mmap_disable = yes<br>
passdb {<br>
driver = pam<br>
}<br>
protocols = imap pop3<br>
service anvil {<br>
client_limit = 203<br>
process_limit = 1<br>
}<br>
service auth {<br>
user = root<br>
}<br>
service imap-login {<br>
chroot = login<br>
client_limit = 10<br>
user = dovecot<br>
vsz_limit = 256 M<br>
}<br>
service pop3-login {<br>
chroot = login<br>
client_limit = 20<br>
user = dovecot<br>
}<br>
ssl = no<br>
syslog_facility = local2<br>
userdb {<br>
driver = passwd<br>
}<br>
verbose_proctitle = yes<br>
protocol pop3 {<br>
mail_max_userip_connections = 20<br>
pop3_logout_format = top=%t/%p, retr=%r/%b, del=%d/%m, size=%s<br>
pop3_uidl_format = %08Xv%08Xu<br>
}<br>
protocol lda {<br>
postmaster_address = <a class="moz-txt-link-abbreviated" href="mailto:postmaster@example.com">postmaster@example.com</a><br>
}<br>
protocol imap {<br>
mail_max_userip_connections = 10<br>
}<br>
</p>
<p>And the other server which is currently running with a load
average of 10.</p>
<p>dovecot -n<br>
# 2.2.13: /etc/dovecot/dovecot.conf<br>
doveconf: Warning: service anvil { client_limit=100 } is lower
than required under max. load (303)<br>
# OS: Linux 4.1.15-server-2.mga5 x86_64 Mageia 4<br>
base_dir = /var/run/dovecot/<br>
disable_plaintext_auth = no<br>
listen = *<br>
lock_method = dotlock<br>
login_greeting = SpamZapper Email ready.<br>
login_log_format_elements = user=<%u> method=%m rip=%r
lip=%l %c<br>
mail_fsync = always<br>
mail_location = maildir:~/Maildir<br>
mail_nfs_index = yes<br>
mail_nfs_storage = yes<br>
mail_privileged_group = mail<br>
mmap_disable = yes<br>
passdb {<br>
driver = pam<br>
}<br>
protocols = imap pop3<br>
service anvil {<br>
client_limit = 100<br>
process_limit = 1<br>
}<br>
service auth {<br>
user = root<br>
}<br>
service imap-login {<br>
chroot = login<br>
client_limit = 48<br>
user = dovecot<br>
vsz_limit = 256 M<br>
}<br>
service pop3-login {<br>
chroot = login<br>
client_limit = 50<br>
user = dovecot<br>
}<br>
ssl = no<br>
syslog_facility = local2<br>
userdb {<br>
driver = passwd<br>
}<br>
verbose_proctitle = yes<br>
protocol pop3 {<br>
mail_max_userip_connections = 50<br>
pop3_logout_format = top=%t/%p, retr=%r/%b, del=%d/%m, size=%s<br>
pop3_uidl_format = %08Xv%08Xu<br>
}<br>
protocol lda {<br>
postmaster_address = <a class="moz-txt-link-abbreviated" href="mailto:postmaster@example.com">postmaster@example.com</a><br>
}<br>
protocol imap {<br>
mail_max_userip_connections = 40<br>
}<br>
</p>
<p>Can you please offer a suggestion on what is happening? The
timeouts to the imap server are frequent due to the load average.</p>
<p>Thank you.<br>
</p>
<div class="moz-signature">-- <br>
-- <br>
--<br>
<br>
Albert E. Whale, CEH CHS CISA CISSP<br>
<b>President - Chief Info Security Officer</b><br>
<a href="http://www.IT-Security-inc.com">IT Security, Inc.</a> - A
Service Disabled Veteran Owned Company - (<b>SDVOSB</b>)<br>
<b>HUBZone Certified</b><br>
<a href="https://www.linkedin.com/in/albertwhale">LinkedIn</a>
Profile<br>
<br>
<br>
Phone: 412-515-3010 | Email: <a class="moz-txt-link-abbreviated"
href="mailto:Albert.Whale@IT-Security-inc.com">Albert.Whale@IT-Security-inc.com</a><br>
Cell: 412-889-6870<br>
<br>
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