Задержки в ProFTPd 1.3.4a

#
# /etc/proftpd/proftpd.conf -- This is a basic ProFTPD configuration file.
# To really apply changes, reload proftpd after modifications, if
# it runs in daemon mode. It is not required in inetd/xinetd mode.
# 
# Includes DSO modules
Include /etc/proftpd/modules.conf
# Set off to disable IPv6 support which is annoying on IPv4 only boxes.  (Если не пользуетесь IPv6, то лучше установите значение off)
UseIPv6                on   
# If set on you can experience a longer connection delay in many cases.  (В настоящее время протоколом RFC1413 никто не пользуется, # поэтому отключаем.)
IdentLookups            off
ServerName            "FTP Server Debian"  # Имя сервера. Выводит при подключении  клиенту.
ServerType             standalone 
# Тип состояния запуска/работы. Standalone - автономный режим работы (используют на  
#серверах. Потребляет меньше ресурсов.) Inetd - супердемон.  Выбирая между этими двумя режимами, учитывайте, что при работе #через inetd расходуется много ресурсов на запуск процесса proftpd, который происходит при каждом обращении к порту. Таким #образом, на сильнозагруженных серверах предпочтительнее использование автономного режима.
DeferWelcome            off
MultilineRFC2228        on
DefaultServer            on
ShowSymlinks            on
TimeoutNoTransfer        600
TimeoutStalled            600
TimeoutIdle            1200
DisplayLogin                    welcome.msg
DisplayChdir                   .message true
ListOptions                    "-ls"  
# По умолчанию значение стояло "-l" . "-ls" если хотите, чтобы все файлы отображались (например, .htaccess)
DenyFilter            \*.*/
# Use this to jail all users in their homes 
DefaultRoot            ~          # закрываем пользователя в его директории
RootLogin   off              # запрещаем вход от имени root
# Users require a valid shell listed in /etc/shells to login.
# Use this directive to release that constrain.
RequireValidShell        on    # включаем проверку по shell, только если авторизация происходит по данным пользователя, который 
#существует в системе.
# Port 21 is the standard FTP port.   По умолчанию порт у сервера 21. Можно изменить на свой вкус.
Port                21    
# In some cases you have to specify passive ports range to by-pass
# firewall limitations. Ephemeral ports can be used for that, but
# feel free to use a more narrow range.   
# Открываем порты для пассивного метода обмена данными. Обычно значения остаются по умолчанию.
PassivePorts                  49152 65534                 
# If your host was NATted, this option is useful in order to
# allow passive tranfers to work. You have to use your public
# address and opening the passive ports used on your firewall as well.
# В этой строке указываем внешний IP адрес роутера/маршрутизатора за которым стоит сервер.
MasqueradeAddress        xx.xx.xx.xx  
# This is useful for masquerading address with dynamic IPs:
# refresh any configured MasqueradeAddress directives every 8 hours
<IfModule mod_dynmasq.c>
# DynMasqRefresh 28800
</IfModule>
# To prevent DoS attacks, set the maximum number of child processes
# to 30.  If you need to allow more than 30 concurrent connections
# at once, simply increase this value.  Note that this ONLY works
# in standalone mode, in inetd mode you should use an inetd server
# that allows you to limit maximum number of processes per service
# (such as xinetd)
# Устанавливаем значение одновременно создаваемых процессов. Защита от DDoS атак.
MaxInstances            30
# Set the user and group that the server normally runs at.
User                proftpd
Group                nogroup
# Umask 022 is a good standard umask to prevent new files and dirs
# (second parm) from being group and world writable.
Umask                022  022
# Normally, we want files to be overwriteable.
AllowOverwrite            on
# Uncomment this if you are using NIS or LDAP via NSS to retrieve passwords:
# PersistentPasswd        off
# This is required to use both PAM-based authentication and local passwords
# AuthOrder            mod_auth_pam.c* mod_auth_unix.c
# Be warned: use of this directive impacts CPU average load!
# Uncomment this if you like to see progress and transfer rate with ftpwho
# in downloads. That is not needed for uploads rates.
#
# UseSendFile            off
TransferLog /var/log/proftpd/xferlog
SystemLog   /var/log/proftpd/proftpd.log
# Logging onto /var/log/lastlog is enabled but set to off by default
#UseLastlog on
UseFtpUsers  on  # Запрещаем пользователям из /etc/ftpusers доступ к FTP серверу.
UseReverseDNS  off   # Может быть задержка из-за включения этой опции. При обмене в пассивном режиме происходит поиск DNS #адресов/имен IP адреса пользователя/клиента
# In order to keep log file dates consistent after chroot, use timezone info
# from /etc/localtime.  If this is not set, and proftpd is configured to
# chroot (e.g. DefaultRoot or <Anonymous>), it will use the non-daylight
# savings timezone regardless of whether DST is in effect.
#SetEnv TZ :/etc/localtime
<IfModule mod_quotatab.c>
QuotaEngine off
</IfModule>
<IfModule mod_ratio.c>
Ratios off
</IfModule>
# Delay engine reduces impact of the so-called Timing Attack described in
# http://www.securityfocus.com/bid/11430/discuss
# It is on by default. 
<IfModule mod_delay.c>
DelayEngine on
</IfModule>
<IfModule mod_ctrls.c>
ControlsEngine        off
ControlsMaxClients    2
ControlsLog           /var/log/proftpd/controls.log
ControlsInterval      5
ControlsSocket        /var/run/proftpd/proftpd.sock
</IfModule>
<IfModule mod_ctrls_admin.c>
AdminControlsEngine off
</IfModule>
#
# Alternative authentication frameworks
#
#Include /etc/proftpd/ldap.conf
#Include /etc/proftpd/sql.conf
#
# This is used for FTPS connections
#
#Include /etc/proftpd/tls.conf
#
# Useful to keep VirtualHost/VirtualRoot directives separated
#
#Include /etc/proftpd/virtuals.conf
# A basic anonymous configuration, no upload directories.
# <Anonymous ~ftp>
#   User                ftp
#   Group                nogroup
#   # We want clients to be able to login with "anonymous" as well as "ftp"
#   UserAlias            anonymous ftp
#   # Cosmetic changes, all files belongs to ftp user
#   DirFakeUser    on ftp
#   DirFakeGroup on ftp
# 
#   RequireValidShell        off
# 
#   # Limit the maximum number of anonymous logins
#   MaxClients            10
# 
#   # We want 'welcome.msg' displayed at login, and '.message' displayed
#   # in each newly chdired directory.
#   DisplayLogin            welcome.msg
#   DisplayChdir        .message
# 
#   # Limit WRITE everywhere in the anonymous chroot
#   <Directory *>
#     <Limit WRITE>
#       DenyAll
#     </Limit>
#   </Directory>
# 
#   # Uncomment this if you're brave.
#   # <Directory incoming>
#   #   # Umask 022 is a good standard umask to prevent new files and dirs
#   #   # (second parm) from being group and world writable.
#   #   Umask                022  022
#   #            <Limit READ WRITE>
#   #            DenyAll
#   #            </Limit>
#   #            <Limit STOR>
#   #            AllowAll
#   #            </Limit>
#   # </Directory>
# 
# </Anonymous>
# Include other custom configuration files
Include /etc/proftpd/conf.d/