[Dovecot] imap: Error: mmap() failed with file ... dovecot.index.cache: Cannot allocate memory

[Urban Loesch]

Hi,

since some days (about 10) I get the following error in mail error log many, many times:

...
dovecot: imap(user at domain.com pid:32769 session:<dszL7lX1xADD/uGI>): Error: mmap() failed with file /home/dovecotindex/domain.com/user/mailboxes/Trash
/dovecot.index.cache: Cannot allocate memory
....

It's always the same "dovecot.index.cache" file and only for the same heavily used account.
The account is currently used from about 10 different clients with imap at the sime time.

I checked the size of the index cache file and it seems very big:

total 2,7G
-rw------- 1 mailstore mailstore  464 Mär 24 14:36 dovecot.index
-rw------- 1 mailstore mailstore  464 Mär 24 14:36 dovecot.index.backup
-rw------- 1 mailstore mailstore 2,7G Mär 24 14:19 dovecot.index.cache
-rw------- 1 mailstore mailstore  140 Mär 24 14:45 dovecot.index.log
-rw------- 1 mailstore mailstore  89K Mär 24 14:36 dovecot.index.log.2

About 2,7 GB?

To solve the problem temporarily, I removed the index files from the index Trash folder
and Dovecot initialized an index rebuild. Now the size of the index files are small:

total 28K
-rw------- 1 mailstore mailstore  512 Mär 24 14:47 dovecot.index
-rw------- 1 mailstore mailstore  20K Mär 24 15:28 dovecot.index.cache
-rw------- 1 mailstore mailstore 1,2K Mär 24 15:28 dovecot.index.log


But why could the index cache file be so big?

Many thanks
Urban