diff --git a/man/systemd.network.xml b/man/systemd.network.xml
index 9c11c5c3dd..6a7ab696a3 100644
--- a/man/systemd.network.xml
+++ b/man/systemd.network.xml
@@ -4026,6 +4026,27 @@ Token=prefixstable:2002:da8:1::
+
+ RTTSec=
+
+ Specifies the RTT for the filter. Takes a timespan. Typical values are e.g. 100us for
+ extremely high-performance 10GigE+ networks like datacentre, 1ms for non-WiFi LAN connections,
+ 100ms for typical internet connections. Defaults to unset, and the kernel's default will be used.
+
+
+
+
+
+ AckFilter=
+
+ Takes a boolean value, or special value aggressive. If enabled, ACKs in
+ each flow are queued and redundant ACKs to the upstream are dropped. If yes, the filter will always
+ keep at least two redundant ACKs in the queue, while in aggressive mode, it will
+ filter down to a single ACK. This may improve download throughput on links with very asymmetrical
+ rate limits. Defaults to unset, and the kernel's default will be used.
+
+
+
diff --git a/src/network/networkd-network-gperf.gperf b/src/network/networkd-network-gperf.gperf
index 70dead97ab..762eef5b91 100644
--- a/src/network/networkd-network-gperf.gperf
+++ b/src/network/networkd-network-gperf.gperf
@@ -420,6 +420,8 @@ CAKE.PriorityQueueingPreset, config_parse_cake_priority_queueing
CAKE.FirewallMark, config_parse_cake_fwmark, QDISC_KIND_CAKE, 0
CAKE.Wash, config_parse_cake_tristate, QDISC_KIND_CAKE, 0
CAKE.SplitGSO, config_parse_cake_tristate, QDISC_KIND_CAKE, 0
+CAKE.RTTSec, config_parse_cake_rtt, QDISC_KIND_CAKE, 0
+CAKE.AckFilter, config_parse_cake_ack_filter, QDISC_KIND_CAKE, 0
ControlledDelay.Parent, config_parse_qdisc_parent, QDISC_KIND_CODEL, 0
ControlledDelay.Handle, config_parse_qdisc_handle, QDISC_KIND_CODEL, 0
ControlledDelay.PacketLimit, config_parse_controlled_delay_u32, QDISC_KIND_CODEL, 0
diff --git a/src/network/tc/cake.c b/src/network/tc/cake.c
index 8d770b0896..a22a11cce3 100644
--- a/src/network/tc/cake.c
+++ b/src/network/tc/cake.c
@@ -27,6 +27,7 @@ static int cake_init(QDisc *qdisc) {
c->preset = _CAKE_PRESET_INVALID;
c->wash = -1;
c->split_gso = -1;
+ c->ack_filter = _CAKE_ACK_FILTER_INVALID;
return 0;
}
@@ -118,6 +119,18 @@ static int cake_fill_message(Link *link, QDisc *qdisc, sd_netlink_message *req)
return r;
}
+ if (c->rtt > 0) {
+ r = sd_netlink_message_append_u32(req, TCA_CAKE_RTT, c->rtt);
+ if (r < 0)
+ return r;
+ }
+
+ if (c->ack_filter >= 0) {
+ r = sd_netlink_message_append_u32(req, TCA_CAKE_ACK_FILTER, c->ack_filter);
+ if (r < 0)
+ return r;
+ }
+
r = sd_netlink_message_close_container(req);
if (r < 0)
return r;
@@ -605,6 +618,124 @@ int config_parse_cake_fwmark(
return 0;
}
+int config_parse_cake_rtt(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ _cleanup_(qdisc_free_or_set_invalidp) QDisc *qdisc = NULL;
+ CommonApplicationsKeptEnhanced *c;
+ Network *network = ASSERT_PTR(data);
+ usec_t t;
+ int r;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+
+ r = qdisc_new_static(QDISC_KIND_CAKE, network, filename, section_line, &qdisc);
+ if (r == -ENOMEM)
+ return log_oom();
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "More than one kind of queueing discipline, ignoring assignment: %m");
+ return 0;
+ }
+
+ c = CAKE(qdisc);
+
+ if (isempty(rvalue)) {
+ c->rtt = 0;
+ TAKE_PTR(qdisc);
+ return 0;
+ }
+
+ r = parse_sec(rvalue, &t);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Failed to parse '%s=', ignoring assignment: %s",
+ lvalue, rvalue);
+ return 0;
+ }
+ if (t <= 0 || t > UINT32_MAX) {
+ log_syntax(unit, LOG_WARNING, filename, line, 0,
+ "Invalid '%s=', ignoring assignment: %s",
+ lvalue, rvalue);
+ return 0;
+ }
+
+ c->rtt = t;
+ TAKE_PTR(qdisc);
+ return 0;
+}
+
+static const char * const cake_ack_filter_table[_CAKE_ACK_FILTER_MAX] = {
+ [CAKE_ACK_FILTER_NO] = "no",
+ [CAKE_ACK_FILTER_YES] = "yes",
+ [CAKE_ACK_FILTER_AGGRESSIVE] = "aggressive",
+};
+
+DEFINE_PRIVATE_STRING_TABLE_LOOKUP_FROM_STRING_WITH_BOOLEAN(cake_ack_filter, CakeAckFilter, CAKE_ACK_FILTER_YES);
+
+int config_parse_cake_ack_filter(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ _cleanup_(qdisc_free_or_set_invalidp) QDisc *qdisc = NULL;
+ CommonApplicationsKeptEnhanced *c;
+ CakeAckFilter ack_filter;
+ Network *network = ASSERT_PTR(data);
+ int r;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+
+ r = qdisc_new_static(QDISC_KIND_CAKE, network, filename, section_line, &qdisc);
+ if (r == -ENOMEM)
+ return log_oom();
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "More than one kind of queueing discipline, ignoring assignment: %m");
+ return 0;
+ }
+
+ c = CAKE(qdisc);
+
+ if (isempty(rvalue)) {
+ c->ack_filter = _CAKE_ACK_FILTER_INVALID;
+ TAKE_PTR(qdisc);
+ return 0;
+ }
+
+ ack_filter = cake_ack_filter_from_string(rvalue);
+ if (ack_filter < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, ack_filter,
+ "Failed to parse '%s=', ignoring assignment: %s",
+ lvalue, rvalue);
+ return 0;
+ }
+
+ c->ack_filter = ack_filter;
+ TAKE_PTR(qdisc);
+ return 0;
+}
+
const QDiscVTable cake_vtable = {
.object_size = sizeof(CommonApplicationsKeptEnhanced),
.tca_kind = "cake",
diff --git a/src/network/tc/cake.h b/src/network/tc/cake.h
index ff68cedabf..5ca6dc6470 100644
--- a/src/network/tc/cake.h
+++ b/src/network/tc/cake.h
@@ -38,6 +38,14 @@ typedef enum CakePriorityQueueingPreset {
_CAKE_PRESET_INVALID = -EINVAL,
} CakePriorityQueueingPreset;
+typedef enum CakeAckFilter {
+ CAKE_ACK_FILTER_NO = CAKE_ACK_NONE,
+ CAKE_ACK_FILTER_YES = CAKE_ACK_FILTER,
+ CAKE_ACK_FILTER_AGGRESSIVE = CAKE_ACK_AGGRESSIVE,
+ _CAKE_ACK_FILTER_MAX,
+ _CAKE_ACK_FILTER_INVALID = -EINVAL,
+} CakeAckFilter;
+
typedef struct CommonApplicationsKeptEnhanced {
QDisc meta;
@@ -63,7 +71,8 @@ typedef struct CommonApplicationsKeptEnhanced {
/* Other parameters */
int wash;
int split_gso;
-
+ usec_t rtt;
+ CakeAckFilter ack_filter;
} CommonApplicationsKeptEnhanced;
DEFINE_QDISC_CAST(CAKE, CommonApplicationsKeptEnhanced);
@@ -77,3 +86,5 @@ CONFIG_PARSER_PROTOTYPE(config_parse_cake_compensation_mode);
CONFIG_PARSER_PROTOTYPE(config_parse_cake_flow_isolation_mode);
CONFIG_PARSER_PROTOTYPE(config_parse_cake_priority_queueing_preset);
CONFIG_PARSER_PROTOTYPE(config_parse_cake_fwmark);
+CONFIG_PARSER_PROTOTYPE(config_parse_cake_rtt);
+CONFIG_PARSER_PROTOTYPE(config_parse_cake_ack_filter);
diff --git a/test/test-network/conf/25-qdisc-cake.network b/test/test-network/conf/25-qdisc-cake.network
index b13720c6dd..6a1364214d 100644
--- a/test/test-network/conf/25-qdisc-cake.network
+++ b/test/test-network/conf/25-qdisc-cake.network
@@ -21,3 +21,5 @@ PriorityQueueingPreset=diffserv8
FirewallMark=0xff00
Wash=yes
SplitGSO=yes
+RTTSec=1sec
+AckFilter=aggressive
diff --git a/test/test-network/systemd-networkd-tests.py b/test/test-network/systemd-networkd-tests.py
index 7da22349fa..e4e92d5a37 100755
--- a/test/test-network/systemd-networkd-tests.py
+++ b/test/test-network/systemd-networkd-tests.py
@@ -3485,6 +3485,8 @@ class NetworkdTCTests(unittest.TestCase, Utilities):
self.assertIn('overhead 128', output)
self.assertIn('mpu 20', output)
self.assertIn('fwmark 0xff00', output)
+ self.assertIn('rtt 1s', output)
+ self.assertIn('ack-filter-aggressive', output)
@expectedFailureIfModuleIsNotAvailable('sch_codel')
def test_qdisc_codel(self):