I dont't know the capabilities of gmail, but IMAP supports server side search which is quite fast if the Solr full text search plugin for dovecot is used (wiki.dovecot.org/Plugins/FTS/Solr). For debian "dovecot-solr" can be used.
For Android K9-Mail does not really support server side search, Aquamail does and for other mail clients I don't know. Am 1. Dezember 2019 22:18:37 MEZ schrieb John Gateley via dovecot <dovecot@dovecot.org>: >Hello, > >I am using dovecot as an imap server, mail is stored in mail >directories. >Configuration is below. > >One mail directory has about 14 Gb of mail in the inbox and .Sent >directories. > >Searching from an Android phone with gmail is slow or doesn't work (it >times out). > >Is there a configuration for Dovecot that can improve this? A better >e-mail client >for Android? > >Thanks, > >John > > >root@giraffe:~# dovecot --version >2.2.27 (c0f36b0) >root@giraffe:~# doveconf -an ># 2.2.27 (c0f36b0): /etc/dovecot/dovecot.conf ># Pigeonhole version 0.4.16 (fed8554) ># OS: Linux 4.9.0-11-amd64 x86_64 Debian 9.11 >... >mail_location = maildir:~/Maildir >namespace inbox { > inbox = yes > location = > mailbox Drafts { > special_use = \Drafts > } > mailbox Junk { > special_use = \Junk > } > mailbox Sent { > special_use = \Sent > } > mailbox "Sent Messages" { > special_use = \Sent > } > mailbox Trash { > special_use = \Trash > } > prefix = >} >... >protocols = " imap" >... -- Diese Nachricht wurde von meinem Android-Mobiltelefon mit K-9 Mail gesendet.