对比过，最后没办法，大邮箱邮件备份后清空了，这样访问就快了

dovecot -n 输出：

# 1.2.16: /etc/dovecot.conf# OS: Linux 2.6.18-164.el5 x86_64 CentOS release 5.4 (Final) log_path: /var/log/dovecot.logprotocols: pop3s imap imaps managesievelisten(default): *listen(imap): *listen(pop3): *listen(managesieve): 127.0.0.1:2000ssl_ca_file: /etc/pki/tls/certs/iRedMail_CA.pemssl_cert_file: /etc/pki/tls/certs/iRedMail_CA.pemssl_key_file: /etc/pki/tls/private/iRedMail.keylogin_dir: /var/run/dovecot/loginlogin_executable(default): /usr/libexec/dovecot/imap-loginlogin_executable(imap): /usr/libexec/dovecot/imap-loginlogin_executable(pop3): /usr/libexec/dovecot/pop3-loginlogin_executable(managesieve): /usr/libexec/dovecot/managesieve-loginfirst_valid_uid: 501last_valid_uid: 501mail_uid: 501mail_gid: 501mail_location: maildir:/%Lh/Maildir/:INDEX=/%Lh/Maildir/mail_executable(default): /usr/libexec/dovecot/imapmail_executable(imap): /usr/libexec/dovecot/imapmail_executable(pop3): /usr/libexec/dovecot/pop3mail_executable(managesieve): /usr/libexec/dovecot/managesievemail_process_size: 1024mail_plugins(default): quota imap_quota autocreatemail_plugins(imap): quota imap_quota autocreatemail_plugins(pop3): quotamail_plugins(managesieve): mail_plugin_dir(default): /usr/lib64/dovecot/imapmail_plugin_dir(imap): /usr/lib64/dovecot/imapmail_plugin_dir(pop3): /usr/lib64/dovecot/pop3mail_plugin_dir(managesieve): /usr/lib64/dovecot/managesieveimap_client_workarounds(default): tb-extra-mailbox-sepimap_client_workarounds(imap): tb-extra-mailbox-sepimap_client_workarounds(pop3): imap_client_workarounds(managesieve): pop3_client_workarounds(default): pop3_client_workarounds(imap): pop3_client_workarounds(pop3): outlook-no-nuls oe-ns-eohpop3_client_workarounds(managesieve): namespace: type: private separator: / inbox: yes list: yes subscriptions: yesnamespace: type: shared separator: / prefix: Shared/%%u/ location: maildir:/%%Lh/Maildir/:INDEX=/%%Lh/Maildir/Shared/%%u list: children subscriptions: yeslda: postmaster_address: root auth_socket_path: /var/run/dovecot/auth-master mail_plugins: quota sieve autocreate sieve_global_path: /data/vmail/sieve/dovecot.sieve log_path: /var/log/sieve.logauth default: mechanisms: plain login default_realm: baifendian.com user: vmail passdb: driver: ldap args: /etc/dovecot-ldap.conf userdb: driver: ldap args: /etc/dovecot-ldap.conf socket: type: listen client: path: /var/spool/postfix/dovecot-auth mode: 438 user: postfix group: postfix master: path: /var/run/dovecot/auth-master mode: 438 user: vmail group: vmailplugin: quota_warning: storage=85%% /usr/local/bin/dovecot-quota-warning.sh 85 quota_warning2: storage=90%% /usr/local/bin/dovecot-quota-warning.sh 90 quota_warning3: storage=95%% /usr/local/bin/dovecot-quota-warning.sh 95 quota: dict:user::proxy::quotadict quota_rule: *:storage=0 expire: Trash 7 Trash/* 7 Junk 30 expire_dict: proxy::expire auth_socket_path: /var/run/dovecot/auth-master sieve: /data/vmail/sieve/%Ld/%Ln/dovecot.sieve autocreate: INBOX autocreate2: Sent autocreate3: Trash autocreate4: Drafts autocreate5: Junk autosubscribe: INBOX autosubscribe2: Sent autosubscribe3: Trash autosubscribe4: Drafts autosubscribe5: Junk acl: vfile acl_shared_dict: proxy::acl sieve: /data/vmail/sieve/%Ld/%Ln/dovecot.sieve sieve_dir: /data/vmail/sieve/%Ld/%Ln/dict: expire: db:/var/lib/dovecot/expire/expire.db quotadict: mysql:/etc/dovecot-used-quota.conf acl: mysql:/etc/dovecot-share-folder.conf