diff options
| -rw-r--r-- | man/systemd.socket.xml | 41 | ||||
| -rw-r--r-- | src/core/dbus-socket.c | 1 | ||||
| -rw-r--r-- | src/core/load-fragment-gperf.gperf.m4 | 1 | ||||
| -rw-r--r-- | src/core/socket.c | 12 | ||||
| -rw-r--r-- | src/core/socket.h | 1 |
5 files changed, 56 insertions, 0 deletions
diff --git a/man/systemd.socket.xml b/man/systemd.socket.xml index 5efb398b09..4483905832 100644 --- a/man/systemd.socket.xml +++ b/man/systemd.socket.xml @@ -546,6 +546,47 @@ </varlistentry> <varlistentry> + <term><varname>DeferAccept=</varname></term> + + <listitem><para>Takes time (in + seconds) as argument. If set, the + listening process will be awakened + only when data arrives on the socket, + and not immediately when connection is + established. When this option is set, + the + <constant>TCP_DEFER_ACCEPT</constant> + socket option will be used (see + <citerefentry><refentrytitle>tcp</refentrytitle><manvolnum>7</manvolnum></citerefentry>), + and the kernel will ignore initial ACK + packets without any data. The argument + specifies the approximate amount of + time the kernel should wait for + incoming data before falling back to + the normal behaviour of honouring + empty ACK packets. This option is + beneficial for protocols where the + client sends the data first (e.g. + HTTP, in contrast to SMTP), because + the server process will not be woken + up unnecessarily before it can take + any action. + </para> + + <para>If the client also uses the + <constant>TCP_DEFER_ACCEPT</constant> + option, the latency of the initial + connection may be reduced, because the + kernel will send data in the final + packet establishing the connection + (the third packet in the "three-way + handshake").</para> + + <para>Disabled by default.</para> + </listitem> + </varlistentry> + + <varlistentry> <term><varname>ReceiveBuffer=</varname></term> <term><varname>SendBuffer=</varname></term> <listitem><para>Takes an integer diff --git a/src/core/dbus-socket.c b/src/core/dbus-socket.c index bdf111c9e3..cc55b8d71b 100644 --- a/src/core/dbus-socket.c +++ b/src/core/dbus-socket.c @@ -100,6 +100,7 @@ const sd_bus_vtable bus_socket_vtable[] = { SD_BUS_PROPERTY("KeepAliveTime", "t", bus_property_get_usec, offsetof(Socket, keep_alive_time), SD_BUS_VTABLE_PROPERTY_CONST), SD_BUS_PROPERTY("KeepAliveInterval", "t", bus_property_get_usec, offsetof(Socket, keep_alive_interval), SD_BUS_VTABLE_PROPERTY_CONST), SD_BUS_PROPERTY("KeepAliveProbes", "u", bus_property_get_unsigned, offsetof(Socket, keep_alive_cnt), SD_BUS_VTABLE_PROPERTY_CONST), + SD_BUS_PROPERTY("DeferAccept" , "t", bus_property_get_usec, offsetof(Socket, defer_accept), SD_BUS_VTABLE_PROPERTY_CONST), SD_BUS_PROPERTY("Priority", "i", bus_property_get_int, offsetof(Socket, priority), SD_BUS_VTABLE_PROPERTY_CONST), SD_BUS_PROPERTY("ReceiveBuffer", "t", bus_property_get_size, offsetof(Socket, receive_buffer), SD_BUS_VTABLE_PROPERTY_CONST), SD_BUS_PROPERTY("SendBuffer", "t", bus_property_get_size, offsetof(Socket, send_buffer), SD_BUS_VTABLE_PROPERTY_CONST), diff --git a/src/core/load-fragment-gperf.gperf.m4 b/src/core/load-fragment-gperf.gperf.m4 index 67bd0e5209..b4e2b25743 100644 --- a/src/core/load-fragment-gperf.gperf.m4 +++ b/src/core/load-fragment-gperf.gperf.m4 @@ -234,6 +234,7 @@ Socket.KeepAlive, config_parse_bool, 0, Socket.KeepAliveTime, config_parse_sec, 0, offsetof(Socket, keep_alive_time) Socket.KeepAliveInterval, config_parse_sec, 0, offsetof(Socket, keep_alive_interval) Socket.KeepAliveProbes, config_parse_unsigned, 0, offsetof(Socket, keep_alive_cnt) +Socket.DeferAccept, config_parse_sec, 0, offsetof(Socket, defer_accept) Socket.NoDelay, config_parse_bool, 0, offsetof(Socket, no_delay) Socket.Priority, config_parse_int, 0, offsetof(Socket, priority) Socket.ReceiveBuffer, config_parse_iec_size, 0, offsetof(Socket, receive_buffer) diff --git a/src/core/socket.c b/src/core/socket.c index d6d9821f57..a16b20d739 100644 --- a/src/core/socket.c +++ b/src/core/socket.c @@ -613,6 +613,12 @@ static void socket_dump(Unit *u, FILE *f, const char *prefix) { "%sKeepAliveProbes: %u\n", prefix, s->keep_alive_cnt); + if(s->defer_accept) + fprintf(f, + "%sDeferAccept: %s\n", + prefix, format_timespan(time_string, FORMAT_TIMESPAN_MAX, + s->defer_accept, USEC_PER_SEC)); + LIST_FOREACH(port, p, s->ports) { if (p->type == SOCKET_SOCKET) { @@ -828,6 +834,12 @@ static void socket_apply_socket_options(Socket *s, int fd) { log_warning_unit(UNIT(s)->id, "TCP_KEEPCNT failed: %m"); } + if (s->defer_accept) { + int value = s->defer_accept / USEC_PER_SEC; + if (setsockopt(fd, SOL_TCP, TCP_DEFER_ACCEPT, &value, sizeof(value)) < 0) + log_warning_unit(UNIT(s)->id, "TCP_DEFER_ACCEPT failed: %m"); + } + if (s->no_delay) { int b = s->no_delay; if (setsockopt(fd, SOL_TCP, TCP_NODELAY, &b, sizeof(b)) < 0) diff --git a/src/core/socket.h b/src/core/socket.h index 8871eb1ca3..eede70564a 100644 --- a/src/core/socket.h +++ b/src/core/socket.h @@ -105,6 +105,7 @@ struct Socket { usec_t timeout_usec; usec_t keep_alive_time; usec_t keep_alive_interval; + usec_t defer_accept; ExecCommand* exec_command[_SOCKET_EXEC_COMMAND_MAX]; ExecContext exec_context; |