this is not the answer you are looking for but comes from years and
years of experience with mail servers in general (cyrus first then
dovecot)
First off imap clients can handle emails counts but vary on
performance
1. outlook for example is completely useless above 1000 count per
folder/sub folder, imap was kinda supported to outlook 2010 but
after 2012 fell off largely due to microsoft pushing their sync
& exchange servers.
2. thunderbird will and can handle 10000~30000 emails but anything
above 10000 really should be split into a subfolder, i usually take
the inbox and split into the year of the messages to keep into a
subfolder like 2020,2021 etc
3. apple mail and iphone related seem to handle large emails boxes
ok but will slow down above the 1000+ per folder limit
4. android you need to run bluemail or something like that but again
limits are like the iphone for around 1000 per folder, generic imap
client does not work well with android.
As for the 200,000+ emails in the inbox no email system was ever
designed for that - ever.
It needs to be understood that pending how your server hdd's are
formatted (nfs, ufs, zfs etc) will directly effect the speed of
email retreivals.
nfs being the slowest (dependant on network speeds, server speeds
etc)
ufs is the old style unix partitions, ufs works ok but you need to
tweek certain settings for how many inodes can be in memory at any
one time to i believe a max of 10,000 (freebsd, other systems will
vary)
zfs is the best as it will store dir inode etc into memory in the
system so large file numbers in directories have a faster chance to
respond, again system dependant suggest lots of memory
no system will support 200,000 + emails, even if the server can
handle that and running imap where you only download the headers the
email client would just spin trying to update the email box
constantantly.
forget about trying to index searches etc.
internet speed (even a 100M fibre connection) is also a factor.
this is a sample dir structure from my server
1 email = 1 file in a sub dir.
the operating system is where you are choking on its ability to
handle 200,000 files in one directory is just unsustainable.
if you have to handle that many incoming emails i strongly suggest a
sieve filter that automatically moves incoming emails into a folder
based on the email to keep the counts under control.
I find dovecot can handle email counts better then the old cyrus but
when i ran cyrus i was using ufs file system as well, when i
upgraded to dovecot i had also upgraded to zfs.
# cd cur
[05:39:14] mail18.scom.ca [root:0]
/data/dovecot/users/scom.ca/paul@scom.ca/cur
# ll
total 77333
drwx------ 2 vmail vmail uarch 361B Apr 18 05:35 .
drwx------ 947 vmail vmail uarch 963B Apr 18 05:36 ..
-rw------- 1 vmail vmail uarch 6.4K Feb 20 08:05
1645362302.M163606P37919.mail18.scom.ca,S=6536,W=6687:2,FS
-rw------- 1 vmail vmail uarch 8.9K Feb 20 08:05
1645362302.M535115P37919.mail18.scom.ca,S=9074,W=9224:2,S
-rw------- 1 vmail vmail uarch 5.5K Feb 20 08:05
1645362303.M133625P37919.mail18.scom.ca,S=5632,W=5729:2,S
-rw------- 1 vmail vmail uarch 11K Feb 20 08:05
1645362305.M954336P38787.mail18.scom.ca,S=11438,W=11642:2,S
-rw------- 1 vmail vmail uarch 1.9K Feb 20 08:05
1645362305.M954355P38787.mail18.scom.ca,S=1912,W=1965:2,S
-rw------- 1 vmail vmail uarch 2.3K Feb 20 08:05
1645362306.M417932P37919.mail18.scom.ca,S=2333,W=2413:2,S
-rw------- 1 vmail vmail uarch 2.2K Feb 20 08:05
1645362306.M569866P37919.mail18.scom.ca,S=2287,W=2366:2,S
-rw------- 1 vmail vmail uarch 2.3K Feb 20 08:05
1645362307.M184339P37919.mail18.scom.ca,S=2371,W=2452:2,S
-rw------- 1 vmail vmail uarch 22K Feb 20 08:05
1645362307.M706237P37919.mail18.scom.ca,S=22281,W=22692:2,S
-rw------- 1 vmail vmail uarch 189K Feb 20 08:05
1645362313.M247319P37919.mail18.scom.ca,S=193354,W=196073:2,S
-rw------- 1 vmail vmail uarch 182K Feb 20 08:05
1645362313.M68190P39861.mail18.scom.ca,S=186263,W=188880:2,S
fyi
Happy Monday !!!
Thanks - paul
Paul Kudla
004-1009 Byron Street South
Whitby, Ontario - Canada
L1N 4S3
Toronto 416.642.7266
Main 1.866.411.7266
Fax 1.888.892.7266
On 2022-04-17 05:32, Turritopsis Dohrnii Teo En Ming wrote:
Subject: Both Roundcube and Squirrelmail
webmail cannot search for
anything + cannot open many emails because there are more than
200,000
emails in my Inbox
Good day from Singapore,
I am using Virtualmin/Webmin web hosting control panel in my
Virtual
Private Servers (VPS) in Germany.
[1st issue]
===========
Both Roundcube and Squirrelmail webmail cannot search for
anything
because there are more than 200,000 emails in my Inbox.
Roundcube webmail doesn't show any error. Search results simply
don't
show up after a long time.
However, I got the following error in Squirrelmail webmail
(using
Firefox web browser).
ERROR: Connection dropped by IMAP server.
Query: SEARCH CHARSET ISO-8859-1 ALL SUBJECT "keyword"
[2nd issue]
============
Both Roundcube and Squirrelmail webmail cannot open many emails
because there are more than 200,000 emails in my inbox.
Roundcube webmail gives the following error:
SERVER ERROR!
Could not load message from server.
Squirrelmail webmail gives the following error:
ERROR: Connection dropped by IMAP server.
Query: FETCH 1 BODY[HEADER]
My IMAP server is Dovecot version 2.2.36.
Virtualmin version is 6.17.
Webmin version is 1.990.
Usermin version is 1.834.
Authentic theme version is 19.85.1.
However, using Samsung Email app on my Samsung Galaxy A32 5G
Android
phone, I am able to open emails it seems. Only Roundcube and
Squirrelmail webmail appears to have issues opening emails.
Using
Samsung Email app, I have deleted around 6,000 useless emails so
far
but still unable to search and open emails. Looks like I need to
delete more and more useless emails.
How do I solve the above problems?
I am looking forward to your reply.
Thank you very much.
Mr. Turritopsis Dohrnii Teo En Ming, 44 years old as of 17 April
2022
Sunday, is a TARGETED INDIVIDUAL living in Singapore. He is an
IT
Consultant with a Systems Integrator (SI)/computer firm in
Singapore.
He is an IT enthusiast.
-----BEGIN EMAIL SIGNATURE-----
The Gospel for all Targeted Individuals (TIs):
[The New York Times] Microwave Weapons Are Prime Suspect in Ills
of
U.S. Embassy Workers
Link:
https://www.nytimes.com/2018/09/01/science/sonic-attack-cuba-microwave.html
********************************************************************************************
Singaporean Targeted Individual Mr. Turritopsis Dohrnii Teo En
Ming's
Academic Qualifications as at 14 Feb 2019 and refugee seeking
attempts
at the United Nations Refugee Agency Bangkok (21 Mar 2017), in
Taiwan
(5 Aug 2019) and Australia (25 Dec 2019 to 9 Jan 2020):
[1] https://tdtemcerts.wordpress.com/
[2] https://tdtemcerts.blogspot.sg/
[3] https://www.scribd.com/user/270125049/Teo-En-Ming
-----END EMAIL SIGNATURE-----
Hi there,
Try to increase ulimit for Dovecot and Solr service as well as the
default OS one.
Also, you might want to consider opening a bug report in Roundcube
git repository, if you weren't lucky to have response from here,
Aleksander is active over there.
Good luck.
Zakaria