failed: Cached message size smaller than expected

[Aki Tuomi]

On 23.4.2021 17.52, Hauke Fath wrote:
> On Mon, 19 Apr 2021 14:36:07 +0300 (EEST), Aki Tuomi wrote:
>
> [mbox index corruption]
>
>> None of our customers use mbox and there is no mail corruption in 
>> mbox. Just dovecot cache is disagreeing with the mail contents, which 
>> is automatically healed by removing the cache entry from cache.
> We see that a lot here,
>
> read [...] failed: Cached message size smaller than expected (5074 < 
> 5075, box=INBOX, UID=94)
>
> and it makes for a bad user experience: Clients are hanging while 
> attempting to open the mail, and users have to close the window, or 
> click on another mail then come back to the first one in order to 
> successfully open it. I get a lot of complaints.
>  
>> I am not sure what's going on with that, hard to say without knowing 
>> more about how the system is set up and configured.
> There are longstanding problems with Dovecot mbox indexing. I have a 
> mail here from 2004 reporting issues. ISTR they went away in late 1.x 
> releases (maybe should check with a test install?), then came back with 
> 2.x.
>
> I've seen index problems reported against maildir and Dovecot's custom 
> format. My personal take: If a project cannot fix support of a standard 
> format, I am surely not going to follow them into a vendor lock-in.
>
> Would be great if this could be sorted out.
>
> Cheerio,
> Hauke

We are not removing maildir support, which is a non-proprietary format.
If you are experiencing same issues with maildir using latest dovecot
release, we are happy to look at that.

Aki