lmtp timeout, locks and crashes

[Tom Sommer]

I'm seeing some problems on accounts which get a lot of spam (like, a 
lot).

I get these errors:

Mar 15 10:43:49 lmtp(12390): Error: Timeout (29s) while waiting for lock 
for transaction log file 
/var/spool/mail/dovecot/xxxx/xxxx/dovecot.list.index.log (WRITE lock 
held by pid 12193)

---

Mar 15 10:43:49 lmtp(12034): Error: Transaction log file 
/var/spool/mail/dovecot/xxxxx/xxxx/dovecot.list.index.log: marked 
corrupted

---

Mar 15 10:43:49 lmtp(12391): Error: Transaction log 
/var/spool/mail/dovecot/xxxx/xxxx/dovecot.list.index.log: duplicate 
transaction log sequence (3)

----

Mar 15 10:43:59 lmtp(xxxx at xxxx.dk): Error: Timeout (29s) while waiting 
for lock for transaction log file 
/var/spool/mail/dovecot/xxxx/xxxx/dovecot.list.index.log

----

Mar 15 10:43:51 lmtp(12294): Panic: file mail-transaction-log-file.c: 
line 104 (mail_transaction_log_file_free): assertion failed: 
(!file->locked)
Mar 15 10:43:51 lmtp(12294): Error: Raw backtrace: 
/usr/lib/dovecot/libdovecot.so.0 [0x30d567e07a] -> 
/usr/lib/dovecot/libdovecot.so.0 [0x30d567e0e6] -> 
/usr/lib/dovecot/libdovecot.so.0 [0x30d567d4ac] -> 
/usr/lib/dovecot/libdovecot-storage.so.0 [0x30d5299ca7] -> 
/usr/lib/dovecot/libdovecot-storage.so.0(mail_transaction_logs_clean+0x28) 
[0x30d529b698] -> 
/usr/lib/dovecot/libdovecot-storage.so.0(mail_transaction_log_view_close+0x49) 
[0x30d529a7e9] -> /usr/lib/dovecot/libdovecot-storage.so.0 
[0x30d5293c03] -> 
/usr/lib/dovecot/libdovecot-storage.so.0(mailbox_list_index_refresh_later+0x92) 
[0x30d525af62] -> /usr/lib/dovecot/libdovecot-storage.so.0 
[0x30d52589eb] -> /usr/lib/dovecot/libdovecot-storage.so.0 
[0x30d5259217] -> 
/usr/lib/dovecot/libdovecot-storage.so.0(mailbox_transaction_commit_get_changes+0x54) 
[0x30d52352c4] -> 
/usr/lib/dovecot/libdovecot-storage.so.0(mailbox_transaction_commit+0x16) 
[0x30d5235386] -> 
/usr/lib/dovecot/libdovecot-storage.so.0(mail_user_autoexpunge+0x1f8) 
[0x30d522a9b8] -> 
/usr/lib/dovecot/libdovecot-storage.so.0(mail_user_unref+0x2a) 
[0x30d523a16a] -> dovecot/lmtp [DATA 172.17.165.14] [0x40696b] -> 
dovecot/lmtp [DATA 172.17.165.14] [0x406bd6] -> 
/usr/lib/dovecot/libdovecot.so.0(io_loop_call_io+0x49) [0x30d5690579] -> 
/usr/lib/dovecot/libdovecot.so.0(io_loop_handler_run_internal+0xdc) 
[0x30d5691c3c] -> 
/usr/lib/dovecot/libdovecot.so.0(io_loop_handler_run+0xa9) 
[0x30d56906b9] -> /usr/lib/dovecot/libdovecot.so.0(io_loop_run+0x38) 
[0x30d56909e8] -> 
/usr/lib/dovecot/libdovecot.so.0(master_service_run+0x13) [0x30d562e533] 
-> dovecot/lmtp [DATA 172.17.165.14](main+0x15c) [0x404c8c] -> 
/lib64/libc.so.6(__libc_start_main+0xf4) [0x36aea1d9f4] -> dovecot/lmtp 
[DATA 172.17.165.14] [0x404a79]

----

The data is stored on NFS, with single-node access.

mmap_disable is set to 'yes'

Anyone know how to solve this? or can share some insights.

Running dovecot 2.2.21 (5345f22)

-- 
Tom Sommer