lost track of X messages / socket error

[Edd B. <ed...@th...>]

Hi,

I've been using mbsync for some time now, and every year or so I'm faced with
messages like:

Warning: lost track of 104 pulled message(s)
Warning: lost track of 1 pushed message(s)

Searching the internet, lots of other people have enountered this, and as far
as I can see, the general advice is "don't worry about it".

Problem is, the message doesn't go away when you re-run mbsync.

In the past I think I've just nuked the whole maildir and re-synced from
scratch, but that does seem like a sledge hammer solution.

I also notice:

```
Socket error on imap.gmail.com (142.251.5.109:993): timeout.
```

Not sure if that's caused by the "lost messages" error, or a separate issue.

Running with `-Dn` the log ends like:
```
far side: 41156 messages, 0 recent
Warning: lost track of 1 pushed message(s)
Synchronizing...
>>> 9 APPEND "INBOX" (\Seen) "20-Oct-2022 11:11:03 +0100" {29056725}
+ go ahead
(1 in progress) >>> 10 UID FETCH 110231 (INTERNALDATE BODY.PEEK[])
(2 in progress) >>> 11 UID FETCH 110283 (INTERNALDATE BODY.PEEK[])
(3 in progress) >>> 12 UID FETCH 110284 (INTERNALDATE BODY.PEEK[])
Socket error on imap.gmail.com (74.125.133.108:993): timeout.
```

Changing the pipeline depth from 4 to 1, it becomes:
```
far side: 41156 messages, 0 recent
Warning: lost track of 1 pushed message(s)
Synchronizing...
>>> 8 APPEND "INBOX" (\Seen) {29056725}
+ go ahead
Socket error on imap.gmail.com (64.233.184.108:993): timeout.
```

So, seems I can't sync my mail a the moment... Is there a more principled way
to fix this than simply nuking the local maildir?

The problem account is a gmail account. Relevant config below:

```
# GMail
IMAPAccount gmail
Host imap.gmail.com
User <elided>
PassCmd <elided>
SSLType IMAPS
PipelineDepth 4

IMAPStore gmail-remote
Account gmail

MaildirStore gmail-local
Path ~/Mail/gmail/
Inbox ~/Mail/gmail/Inbox

Channel gmail
Far :gmail-remote:
Near :gmail-local:
Patterns <elided>
Create Both
SyncState *
```

This is with the isync-1.4.4p1 package on OpenBSD-current.

Thanks

-- 
Best Regards
Edd Barrett

https://www.theunixzoo.co.uk