mremap_anon() failed: Not enough space

[@lbutlr]

On 20 Jun 2019, at 07:46, Dave McGuire via dovecot <dovecot at dovecot.org> wrote:
> On 6/20/19 6:07 AM, @lbutlr via dovecot wrote:
>>> Jun 19 14:47:31 <hostname> dovecot: [ID 583609 local0.error]
>>> imap(<address>): Error:
>>> mremap_anon(/var/mail/<domain>/<uname>/mailboxes/INBOX/Trash/dbox-Mails/dovecot.index.cache,
>>> 255557632) failed: Not enough space
>>> 
>>> I'm running 2.2.36.1 under Solaris 10 (patched to current) on
>>> UltraSPARC.  There's plenty of memory, plenty of swap, and plenty of
>>> disk, but this is a fairly busy mail server.
>> 
>> Are you sure there is plenty of space on /var/mail/ ? Because that should only show up when the mount point is full.
> 
>  Yes, there's about 3TB available there.
> 
>> Also, what is your definition of “plenty”? (I have some index files in the 50MB range, and I am sure there are people with indexes much larger than that).
> 
>  The index file in question was 255MB.  In desperation, and watching
> the other thread going on about index files, I moved dovecot.index.cache
> aside and let it be re-created.  No further issues have appeared in the
> log, and the new dovecot.index.cache file (created yesterday) has grown
> to about 120KB.
> 
>  The spool in question was about 3GB, with about 100K messages in it.
> I've never seen a dovecot.index.cache file grow so large; does that seem
> reasonable to you?

They seem to grow. As I meant to say, but typoed, I have some in the range of 500MB here (not 50MB, though I have those too). I think deleting the index.cache every now and then is probably reasonable but I don’t know what a reasonable time frame is. Yearly? I might start with yearly. I removed them all yeterday shortly after posting to see how things would go.

# exa -l /usr/local/virtual/*/*/.*/dove* | sort -k 2 -h   

They are much much smaller (under 10MB), but I am sure they will grow as users access the larger folders on their mail store (it’s not unusual for user to have 4-5GB of email in their .Archive mail store).

It’s also possible that the cache files USED to grow quite large in previous versions and that now they are much more reasonable, but the only way to reset their size appears to be to delete them and let dovecot rebuild them.

Anyway, if you get any sort of index errors in the future the first trouble shooting step is to delete the index file. If that doesn’t work, delete all the index files for that folder. Then if that still didn’t fix it you start looking for other causes.