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*/
#include "tcp_includes.h"
#include <netinet/tcp_sysctls.h>
#include <netinet/tcp_var.h>
#include <sys/sysctl.h>
SYSCTL_SKMEM_TCP_INT(OID_AUTO, cubic_tcp_friendliness, CTLFLAG_RW | CTLFLAG_LOCKED,
int, tcp_cubic_tcp_friendliness, 0, "Enable TCP friendliness");
SYSCTL_SKMEM_TCP_INT(OID_AUTO, cubic_fast_convergence, CTLFLAG_RW | CTLFLAG_LOCKED,
int, tcp_cubic_fast_convergence, 0, "Enable fast convergence");
SYSCTL_SKMEM_TCP_INT(OID_AUTO, cubic_use_minrtt, CTLFLAG_RW | CTLFLAG_LOCKED,
int, tcp_cubic_use_minrtt, 0, "use a min of 5 sec rtt");
SYSCTL_SKMEM_TCP_INT(OID_AUTO, cubic_minor_fixes, CTLFLAG_RW | CTLFLAG_LOCKED,
int, tcp_cubic_minor_fixes, 1, "Minor fixes to TCP Cubic");
SYSCTL_SKMEM_TCP_INT(OID_AUTO, cubic_rfc_compliant, CTLFLAG_RW | CTLFLAG_LOCKED,
int, tcp_cubic_rfc_compliant, 1, "RFC Compliance for TCP Cubic");
SYSCTL_SKMEM_TCP_INT(OID_AUTO, rack, CTLFLAG_RW | CTLFLAG_LOCKED,
int, tcp_rack, 0, "TCP RACK");
/* Target queuing delay in milliseconds. This includes the processing
* and scheduling delay on both of the end-hosts. A LEDBAT sender tries
* to keep queuing delay below this limit. When the queuing delay
* goes above this limit, a LEDBAT sender will start reducing the
* congestion window.
*
* The LEDBAT draft says that target queue delay MUST be 100 ms for
* inter-operability.
* As we are enabling LEDBAT++ by default, we are updating the target
* queuing delay to 60ms as recommended by the draft.
*/
SYSCTL_SKMEM_TCP_INT(OID_AUTO, bg_target_qdelay, CTLFLAG_RW | CTLFLAG_LOCKED,
int, target_qdelay, 40, "Target queuing delay");
/* Allowed increase and tether are used to place an upper bound on
* congestion window based on the amount of data that is outstanding.
* This will limit the congestion window when the amount of data in
* flight is little because the application is writing to the socket
* intermittently and is preventing the connection from becoming idle .
*
* max_allowed_cwnd = allowed_increase + (tether * flight_size)
* cwnd = min(cwnd, max_allowed_cwnd)
*
* 'Allowed_increase' parameter is set to 8. If the flight size is zero, then
* we want the congestion window to be at least 8 packets to reduce the
* delay induced by delayed ack. This helps when the receiver is acking
* more than 2 packets at a time (stretching acks for better performance).
*
* 'Tether' is also set to 2. We do not want this to limit the growth of cwnd
* during slow-start.
*/
SYSCTL_SKMEM_TCP_INT(OID_AUTO, bg_allowed_increase, CTLFLAG_RW | CTLFLAG_LOCKED,
int, tcp_ledbat_allowed_increase, 8,
"Additive constant used to calculate max allowed congestion window");
/* Left shift for cwnd to get tether value of 2 */
SYSCTL_SKMEM_TCP_INT(OID_AUTO, bg_tether_shift, CTLFLAG_RW | CTLFLAG_LOCKED,
int, tcp_ledbat_tether_shift, 1, "Tether shift for max allowed congestion window");
/* Start with an initial window of 2. This will help to get more accurate
* minimum RTT measurement in the beginning. It will help to probe
* the path slowly and will not add to the existing delay if the path is
* already congested. Using 2 packets will reduce the delay induced by delayed-ack.
*/
SYSCTL_SKMEM_TCP_INT(OID_AUTO, bg_ss_fltsz, CTLFLAG_RW | CTLFLAG_LOCKED,
uint32_t, bg_ss_fltsz, 2, "Initial congestion window for background transport");
SYSCTL_SKMEM_TCP_INT(OID_AUTO, ledbat_plus_plus, CTLFLAG_RW | CTLFLAG_LOCKED,
int, tcp_ledbat_plus_plus, 1, "Use LEDBAT++");
SYSCTL_SKMEM_TCP_INT(OID_AUTO, rledbat, CTLFLAG_RW | CTLFLAG_LOCKED,
int, tcp_rledbat, 1, "Use Receive LEDBAT");
int tcp_cc_debug;
SYSCTL_INT(_net_inet_tcp, OID_AUTO, cc_debug, CTLFLAG_RW | CTLFLAG_LOCKED,
&tcp_cc_debug, 0, "Enable debug data collection");
extern struct tcp_cc_algo tcp_cc_newreno;
SYSCTL_INT(_net_inet_tcp, OID_AUTO, newreno_sockets,
CTLFLAG_RD | CTLFLAG_LOCKED, &tcp_cc_newreno.num_sockets,
0, "Number of sockets using newreno");
extern struct tcp_cc_algo tcp_cc_ledbat;
SYSCTL_INT(_net_inet_tcp, OID_AUTO, background_sockets,
CTLFLAG_RD | CTLFLAG_LOCKED, &tcp_cc_ledbat.num_sockets,
0, "Number of sockets using background transport");
#if (DEVELOPMENT || DEBUG)
SYSCTL_SKMEM_TCP_INT(OID_AUTO, use_ledbat,
CTLFLAG_RW | CTLFLAG_LOCKED, int, tcp_use_ledbat, 0,
"Use TCP LEDBAT for testing");
#else
SYSCTL_SKMEM_TCP_INT(OID_AUTO, use_ledbat,
CTLFLAG_RD | CTLFLAG_LOCKED, int, tcp_use_ledbat, 0,
"Use TCP LEDBAT for testing");
#endif /* (DEVELOPMENT || DEBUG) */
extern struct tcp_cc_algo tcp_cc_cubic;
SYSCTL_INT(_net_inet_tcp, OID_AUTO, cubic_sockets,
CTLFLAG_RD | CTLFLAG_LOCKED, &tcp_cc_cubic.num_sockets,
0, "Number of sockets using cubic");
SYSCTL_SKMEM_TCP_INT(OID_AUTO, use_newreno,
CTLFLAG_RW | CTLFLAG_LOCKED, int, tcp_use_newreno, 0,
"Use TCP NewReno by default");