Aki Tuomi <aki.tuomi at dovecot.fi> writes:
> On 24 February 2018 at 12:45 Neil Jerram < neil at
ossau.homelinux.net> wrote:
>
> Please could you help me to understand and fix why my dovecot IMAP
> performance is so bad? I've read through a lot of the
> performance-related material on the website, but I don't think that
any
> of it could account for slowness at the level that I am seeing.
>
> The simplest scenario is moving a message from my Inbox to another IMAP
> folder. Using Gnus as the client, the whole UI freezes for about 2
> minutes (which I assume is until the move is complete), and journalctl
> on the dovecot server says:
>
> Feb 24 10:24:24 arudy dovecot[1712]: imap(neil): Warning: Transaction log
file /home/neil/dovecot-mail/.imap/INBOX/dovecot.index.log was locked for 98
seconds (Mailbox was synchronized)
>
> or the same message with (rotating while syncing).
>
> There must be something badly wrong in my setup, or perhaps in the spec
> of the server that dovecot is running on. What should I look at to
> start understanding this better?
>
> Many thanks - Neil
>
> Can you tell a bit more about your environment? Sounds like io issue
Thanks for your reply. I'm not sure exactly what you have in mind, but
here are some starting points:
arudy:~# uname -a
Linux arudy 4.13.0-1-686-pae #1 SMP Debian 4.13.4-2 (2017-10-15) i686 GNU/Linux
arudy:~# dovecot -n
# 2.2.32 (dfbe293d4): /etc/dovecot/dovecot.conf
# Pigeonhole version 0.4.20 (7cd71ba)
# OS: Linux 4.13.0-1-686-pae i686 Debian buster/sid
auth_mechanisms = plain login
auth_username_format = %Ln
auth_verbose = yes
login_trusted_networks = 192.168.11.8
mail_access_groups = mail
mail_fsync = never
mail_location = mbox:~/dovecot-mail:INBOX=/var/mail/%u
namespace inbox {
inbox = yes
location =
mailbox Drafts {
special_use = \Drafts
}
mailbox Junk {
special_use = \Junk
}
mailbox Sent {
special_use = \Sent
}
mailbox "Sent Messages" {
special_use = \Sent
}
mailbox Trash {
special_use = \Trash
}
prefix =
}
passdb {
driver = pam
}
plugin {
antispam_backend = dspam
antispam_dspam_args = --deliver;--user;%u
antispam_dspam_binary = /usr/bin/dspam
antispam_signature = X-DSPAM-Signature
antispam_signature_missing = error
antispam_spam = Spam
antispam_trash = trash;Trash;Deleted Items; Deleted Messages
fts = solr
fts_solr = url=http://localhost:8080/solr/
sieve = file:~/sieve;active=~/.dovecot.sieve
}
postmaster_address = postmaster at ossau.homelinux.net
protocols = " imap lmtp"
service auth {
unix_listener /var/spool/postfix/private/auth {
group = postfix
mode = 0666
user = postfix
}
}
service lmtp {
unix_listener /var/spool/postfix/private/dovecot-lmtp {
group = postfix
mode = 0600
user = postfix
}
}
ssl_cert = </etc/dovecot/cert.pem
ssl_key = # hidden, use -P to show it
userdb {
driver = passwd
}
protocol lmtp {
mail_fsync = optimized
}
protocol lda {
mail_fsync = optimized
}
arudy:~# cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 8
model name : Pentium III (Coppermine)
stepping : 6
microcode : 0x8
cpu MHz : 935.497
cache size : 256 KB
physical id : 0
siblings : 1
core id : 0
cpu cores : 1
apicid : 0
initial apicid : 0
fdiv_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 2
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca cmov pse36 mmx fxsr
sse cpuid
bugs :
bogomips : 1870.99
clflush size : 32
cache_alignment : 32
address sizes : 36 bits physical, 32 bits virtual
power management:
arudy:~# free
total used free shared buff/cache available
Mem: 248808 31572 4080 2576 213156 205880
Swap: 763052 20480 742572