My CentOS system, used for PHPList, accumulates incoming mail in this path: /var/qmail/mailnames/example.com/noreply/Maildir/cur
There used to be hundreds of thousands of emails in this mailbox, they were bounce emails meant for bounce processing by PHPList, but PHPList was choking on them. So I used cleanup-maildir script to mass-remove emails. Now I see that the cur directory is empty, (ls -l weirdly takes about 10 seconds to return with "total 0") and yet it shows a large size. My Plesk panel also shows that the mail account is still occupying many GB. What do I need to do?
[root@server-1012263-1 cur]# pwd
/var/qmail/mailnames/example.com/noreply/Maildir/cur
[root@server-1012263-1 cur]# ls -al
total 72520
drwx------ 2 popuser popuser 74199040 Jan 8 18:10 .
drwx------ 10 popuser popuser 4096 Jan 8 18:15 ..
[root@server-1012263-1 cur]# cd ..
[root@server-1012263-1 Maildir]# pwd
/var/qmail/mailnames/example.com/noreply/Maildir
[root@server-1012263-1 Maildir]# ls -al
total 81432
drwx------ 10 popuser popuser 4096 Jan 8 18:20 .
drwx------ 6 popuser popuser 4096 Feb 9 2017 ..
drwx------ 6 popuser popuser 4096 Apr 23 2018 .auto replies
-rwxr-xr-x 1 popuser popuser 18968 Jun 3 2016 cleanup-maildir
drwx------ 2 popuser popuser 4096 Jul 18 2017 courierimapkeywords
-rw-r--r-- 1 popuser popuser 30 Jul 14 2015 courierimapsubscribed
-rw-r--r-- 1 popuser popuser 2216005 Mar 9 2016 courierimapuiddb
-rw-r--r-- 1 popuser popuser 666592 Jun 5 2016 courierpop3dsizelist
drwx------ 2 popuser popuser 74199040 Jan 8 18:10 cur
-rw------- 1 popuser popuser 432 Jan 8 18:10 dovecot.index
-rw------- 1 popuser popuser 5250820 Jan 8 18:20 dovecot.index.cache
-rw------- 1 popuser popuser 6196 Jan 8 18:20 dovecot.index.log
-rw------- 1 popuser popuser 33028 Jan 8 18:10 dovecot.index.log.2
-rw------- 1 popuser popuser 720 Apr 23 2018 dovecot.list.index.log
-rw------- 1 popuser popuser 12632 Jan 8 18:20 dovecot-uidlist
-rw------- 1 popuser popuser 8 Apr 23 2018 dovecot-uidvalidity
-r--r--r-- 1 popuser popuser 0 Jun 6 2016 dovecot-uidvalidity.57547a5e
drwx------ 5 popuser popuser 4096 Aug 11 2017 .Drafts
-rw------- 1 popuser popuser 1910 Jan 8 18:20 maildirsize
drwx------ 2 popuser popuser 839680 Jan 8 18:20 new
drwx------ 6 popuser popuser 4096 Aug 18 2017 .Sent
drwx------ 6 popuser popuser 4096 Apr 23 2018 .Spam
-rw-r--r-- 1 popuser popuser 18 Jun 5 2016 subscriptions
drwx------ 2 popuser popuser 4096 Jan 8 18:20 tmp
[root@server-1012263-1 Maildir]# cd cur
[root@server-1012263-1 cur]# pwd
/var/qmail/mailnames/example.com/noreply/Maildir/cur
[root@server-1012263-1 cur]# find -type f -exec rm -f {} \;
[root@server-1012263-1 cur]# ls -al
total 72520
drwx------ 2 popuser popuser 74199040 Jan 8 18:25 .
drwx------ 10 popuser popuser 4096 Jan 8 18:25 ..
Screenshot of my Plesk panel showing 15GB: https://i.imgur.com/oCToAWB.png