[Dovecot] dovecot index errors since 2.1.12

[Morten Stevens]

Hi,

After upgrading to dovecot 2.1.12, I see a lot of these errors:

# 2.1.12: /etc/dovecot/dovecot.conf
# OS: Linux 2.6.32-279.14.1.el6.x86_64 x86_64 CentOS release 6.3 (Final)
# Filesystem: ext4 with mdbox storage

Dec 10 15:21:04 mail dovecot: imap(user at example.org): Error: Cached 
message size smaller than expected (5010 < 8192)
Dec 10 15:21:04 mail dovecot: imap(user at example.org): Error: Corrupted 
index cache file 
/var/vmail/example.org/user//mdbox/mailboxes/INBOX/Ubuntu/dbox-Mails/dovecot.index.cache: 
Broken physical size for mail UID 27517
Dec 10 15:21:04 mail dovecot: imap(user at example.org): Error: 
read(/var/vmail/example.org/user//mdbox/storage/m.7123) failed: 
Input/output error (FETCH for mailbox INBOX/Ubuntu UID 27517)
Dec 10 15:21:04 mail dovecot: imap(user at example.org): Disconnected: 
Internal error occurred. Refer to server log for more information. 
[2012-12-10 15:21:04] in=3391 out=1383967

Dec 17 21:38:34 mail dovecot: imap(user2 at example.org): Error: Cached 
message size larger than expected (12222 > 12085)
Dec 17 21:38:34 mail dovecot: imap(user2 at example.org): Error: Corrupted 
index cache file 
/var/vmail/example.org/user2//mdbox/mailboxes/LKML/dbox-Mails/dovecot.index.cache: 
Broken physical size for mail UID 216231
Dec 17 21:38:34 mail dovecot: imap(user2 at example.org): Error: 
read(/var/vmail/example.org/user2//mdbox/storage/m.15569) failed: 
Input/output error (FETCH for mailbox LKML UID 216231)
Dec 17 21:38:34 mail dovecot: imap(user2 at example.org): Disconnected: 
Internal error occurred. Refer to server log for more information. 
[2012-12-17 21:38:34] in=4079 out=61996358

Dec 17 21:40:34 mail dovecot: imap(user2 at example.org): Error: Cached 
message size larger than expected (6726 > 5302)
Dec 17 21:40:34 mail dovecot: imap(user2 at example.org): Error: Corrupted 
index cache file 
/var/vmail/example.org/user2//mdbox/mailboxes/Google/dbox-Mails/dovecot.index.cache: 
Broken physical size for mail UID 930834
Dec 17 21:40:34 mail dovecot: imap(user2 at example.org): Error: 
read(/var/vmail/example.org/user2//mdbox/storage/m.15544) failed: 
Input/output error (FETCH for mailbox Google UID 930834)
Dec 17 21:40:34 mail dovecot: imap(user2 at example.org): Disconnected: 
Internal error occurred. Refer to server log for more information. 
[2012-12-17 21:40:34] in=27666 out=29738162

Since the release of dovecot 2.1.x, I have never seen this error 
message. After downgrading to 2.1.10 the error is gone.

Andy ideas?

Best regards,

Morten