[#893] addressed review

ChangeLog

@@ -1,3 +1,11 @@
+1730.	[func]		razvan
+	Added -N command line switch that enables experimental multi-threading
+	support. Number of threads can be specified (e.g. -N8) or Kea can be
+	told to autodetect number of CPU threads (-N0). This feature is
+	experimental. It hasn't been tested extensively and is known to cause
+	problems with DDNS and HA. Do not use in production!
+	(Gitlab #893)
+
 1729.	[func]		razvan
 	The RAII MultiThreadingCriticalSection class is now able to
 	automatically stop and start the packet thread pool in order to

src/bin/dhcp4/ctrl_dhcp4_srv.cc

@@ -169,7 +169,6 @@ ControlledDhcpv4Srv::loadConfigFile(const std::string& file_name) {
                       "processCommand(\"config-set\", json)");
         }
 
-        // @todo enable multi-threading - disabled for now
         bool enabled = false;
         if (srv_thread_count >= 0) {
             enabled = true;

src/bin/dhcp4/dhcp4_messages.cc

@@ -1,4 +1,4 @@
-// File created from ../../../src/bin/dhcp4/dhcp4_messages.mes on Mon Mar 16 2020 18:32
+// File created from ../../../src/bin/dhcp4/dhcp4_messages.mes on Wed Mar 18 2020 16:28
 
 #include <cstddef>
 #include <log/message_types.h>
@@ -226,7 +226,7 @@ const char* values[] = {
     "DHCP4_LEASE_ADVERT", "%1: lease %2 will be advertised",
     "DHCP4_LEASE_ALLOC", "%1: lease %2 has been allocated for %3 seconds",
     "DHCP4_MULTI_THREADING_INFO", "enabled: %1, number of threads: %2, queue size per thread: %3",
-    "DHCP4_MULTI_THREADING_WARNING", "multi-threading support is experimental. Don't use in production environment.",
+    "DHCP4_MULTI_THREADING_WARNING", "The multi-threading feature is experimental. Don't use in production environment.",
     "DHCP4_NCR_CREATE", "%1: DDNS updates enabled, therefore sending name change requests",
     "DHCP4_NCR_CREATION_FAILED", "%1: failed to generate name change requests for DNS: %2",
     "DHCP4_NOT_RUNNING", "DHCPv4 server is not running",

src/bin/dhcp4/dhcp4_messages.h

@@ -1,4 +1,4 @@
-// File created from ../../../src/bin/dhcp4/dhcp4_messages.mes on Mon Mar 16 2020 18:32
+// File created from ../../../src/bin/dhcp4/dhcp4_messages.mes on Wed Mar 18 2020 16:28
 
 #ifndef DHCP4_MESSAGES_H
 #define DHCP4_MESSAGES_H

src/bin/dhcp4/dhcp4_messages.mes

@@ -441,7 +441,7 @@ lifetime.
 This is a message listing some information about the multi-threading parameters
 with which the server is running.
 
-% DHCP4_MULTI_THREADING_WARNING multi-threading support is experimental. Don't use in production environment.
+% DHCP4_MULTI_THREADING_WARNING The multi-threading feature is experimental. Don't use in production environment.
 This is a message warning about the experimental multi-threading feature.
 
 % DHCP4_NCR_CREATE %1: DDNS updates enabled, therefore sending name change requests

src/bin/dhcp4/main.cc

@@ -48,7 +48,7 @@ usage() {
     cerr << "Kea DHCPv4 server, version " << VERSION << endl;
     cerr << endl;
     cerr << "Usage: " << DHCP4_NAME
-         << " -[v|V|W] [-d] [-{c|t} cfgfile] [-p number] [-P number]" << endl;
+         << " -[v|V|W] [-d] [-{c|t} cfgfile] [-p number] [-P number] [-N number]" << endl;
     cerr << "  -v: print version number and exit" << endl;
     cerr << "  -V: print extended version and exit" << endl;
     cerr << "  -W: display the configuration report and exit" << endl;

src/bin/dhcp6/ctrl_dhcp6_srv.cc

@@ -140,7 +140,6 @@ ControlledDhcpv6Srv::loadConfigFile(const std::string& file_name) {
                       "processCommand(\"config-set\", json)");
         }
 
-        // @todo enable multi-threading - disabled for now
         bool enabled = false;
         if (srv_thread_count >= 0) {
             enabled = true;

src/bin/dhcp6/dhcp6_messages.cc

@@ -1,4 +1,4 @@
-// File created from ../../../src/bin/dhcp6/dhcp6_messages.mes on Mon Mar 16 2020 18:36
+// File created from ../../../src/bin/dhcp6/dhcp6_messages.mes on Wed Mar 18 2020 16:30
 
 #include <cstddef>
 #include <log/message_types.h>
@@ -230,7 +230,7 @@ const char* values[] = {
     "DHCP6_LEASE_PD_WITHOUT_DUID", "%1: lease for prefix %2/%3 does not have a DUID",
     "DHCP6_LEASE_RENEW", "%1: lease for address %2 and iaid=%3 has been allocated",
     "DHCP6_MULTI_THREADING_INFO", "enabled: %1, number of threads: %2, queue size per thread: %3",
-    "DHCP6_MULTI_THREADING_WARNING", "multi-threading support is experimental. Don't use in production environment.",
+    "DHCP6_MULTI_THREADING_WARNING", "The multi-threading feature is experimental. Don't use in production environment.",
     "DHCP6_NOT_RUNNING", "IPv6 DHCP server is not running",
     "DHCP6_NO_INTERFACES", "failed to detect any network interfaces",
     "DHCP6_NO_SOCKETS_OPEN", "no interface configured to listen to DHCP traffic",

src/bin/dhcp6/dhcp6_messages.h

@@ -1,4 +1,4 @@
-// File created from ../../../src/bin/dhcp6/dhcp6_messages.mes on Mon Mar 16 2020 18:36
+// File created from ../../../src/bin/dhcp6/dhcp6_messages.mes on Wed Mar 18 2020 16:30
 
 #ifndef DHCP6_MESSAGES_H
 #define DHCP6_MESSAGES_H

src/bin/dhcp6/dhcp6_messages.mes

@@ -488,7 +488,7 @@ IAID.
 This is a message listing some information about the multi-threading parameters
 with which the server is running.
 
-% DHCP6_MULTI_THREADING_WARNING multi-threading support is experimental. Don't use in production environment.
+% DHCP6_MULTI_THREADING_WARNING The multi-threading feature is experimental. Don't use in production environment.
 This is a message warning about the experimental multi-threading feature.
 
 % DHCP6_NOT_RUNNING IPv6 DHCP server is not running

src/bin/dhcp6/main.cc

@@ -48,7 +48,7 @@ usage() {
     cerr << "Kea DHCPv6 server, version " << VERSION << endl;
     cerr << endl;
     cerr << "Usage: " << DHCP6_NAME
-         << " -[v|V|W] [-d] [-{c|t} cfgfile] [-p number] [-P number]" << endl;
+         << " -[v|V|W] [-d] [-{c|t} cfgfile] [-p number] [-P number] [-N number]" << endl;
     cerr << "  -v: print version number and exit." << endl;
     cerr << "  -V: print extended version and exit" << endl;
     cerr << "  -W: display the configuration report and exit" << endl;