TCP_INFOvsWeb100Web10g
Investigate the possible use of TCP_INFO instead of web100/web10g.
struct tcp_info
{
u_int8_t tcpi_state;
u_int8_t tcpi_ca_state;
u_int8_t tcpi_retransmits;
u_int8_t tcpi_probes;
u_int8_t tcpi_backoff;
u_int8_t tcpi_options;
u_int8_t tcpi_snd_wscale : 4, tcpi_rcv_wscale : 4;
u_int32_t tcpi_rto;
u_int32_t tcpi_ato;
u_int32_t tcpi_snd_mss;
u_int32_t tcpi_rcv_mss;
u_int32_t tcpi_unacked;
u_int32_t tcpi_sacked;
u_int32_t tcpi_lost;
u_int32_t tcpi_retrans;
u_int32_t tcpi_fackets;
/* Times. */
u_int32_t tcpi_last_data_sent;
u_int32_t tcpi_last_ack_sent; /* Not remembered, sorry. */
u_int32_t tcpi_last_data_recv;
u_int32_t tcpi_last_ack_recv;
/* Metrics. */
u_int32_t tcpi_pmtu;
u_int32_t tcpi_rcv_ssthresh;
u_int32_t tcpi_rtt;
u_int32_t tcpi_rttvar;
u_int32_t tcpi_snd_ssthresh;
u_int32_t tcpi_snd_cwnd;
u_int32_t tcpi_advmss;
u_int32_t tcpi_reordering;
};
You can find this structure in:
/usr/include/netinet/tcp.h
tcpi_state; /* Possible value:
TCP_ESTABLISHED = 1,
TCP_SYN_SENT,
TCP_SYN_RECV,
TCP_FIN_WAIT1,
TCP_FIN_WAIT2,
TCP_TIME_WAIT,
TCP_CLOSE,
TCP_CLOSE_WAIT,
TCP_LAST_ACK,
TCP_LISTEN,
TCP_CLOSING */
tcpi_ca_state; /* Congestion control state */
tcpi_retransmits; /* Number of unrecovered [RTO] timeouts */
tcpi_probes; /* Unanswered 0 window probes */
tcpi_backoff; /* Backoff */
tcpi_options;
tcpi_snd_wscale /* Window scaling received from sender */
tcpi_rcv_wscale /*Window scaling to send to receiver*/
tcpi_rto; /* Retransmit timeout */
tcpi_ato; /* Predicted tick of soft clock */
tcpi_snd_mss; /* Cached effective mss, not including SACKS*/
tcpi_rcv_mss; /* MSS used for delayed ACK decisions */
tcpi_unacked; /* Packets which are "in flight" */
tcpi_sacked; /* SACK'd packets */
tcpi_lost; /* Lost packets */
tcpi_retrans; /* Retransmitted packets out */
tcpi_fackets; /* FACK'd packets */
tcpi_last_data_sent; /* now – lsndtime (lsndtime → timestamp of last sent data packet (for restart window)) */
tcpi_last_ack_sent; /* Not remembered, sorry. */
tcpi_last_data_recv; /* now – isck_ack.lrcvtime (isck_ack ->Delayed ACK control data; lrcvtime → timestamp of last received data packet) */
tcpi_last_ack_recv; /* now - rcv_tstamp (rcv_tstamp → timestamp of last received ACK (for keepalives)) */
tcpi_pmtu; /* Last pmtu seen by socket (Path Maximum Transmission Unit) */
tcpi_rcv_ssthresh; /* slow start size threshold for receiving (Current window clamp) */
tcpi_rtt; /* Smoothed Round Trip Time (SRTT) */
tcpi_rttvar; /* Medium deviation */
tcpi_snd_ssthresh; /* Slow start size threshold for sending */
tcpi_snd_cwnd; /* Sending congestion window */
tcpi_advmss; /* Advertised Maximum Segment Size (MSS) */
tcpi_reordering; /* Indicates the amount of reordering. Packet reordering metric */
tcpi_rcv_rtt; /* Receiver side RTT estimation */
tcpi_rcv_space; /* Receiver queue space */
tcpi_total_retrans; /* Total retransmits for entire connection */
TCP_INFO structure is filled in the tcp_get_info() function.You can find it in kernel source:
/lib/modules/`uname -r`/build/net/ipv4/tcp.c
Most of the data is copied from tcp_sock and inet_connection_sock structure.
tcp_sock struct you can find in:
/lib/modules/`uname -r`/build/include/linux/tcp.h
or
/lib/modules/`uname -r`/build/include/net/tcp.h
inet_connection_sock structure is in:
/lib/modules/`uname -r`/build/include/net/inet_connection_sock.h
second column: equivalent variables in Web100/10g or how it's calculated
third column: equivalent variables in TCP_INFO
| UI | Web100/10g variables | TCP_INFO |
|---|---|---|
| status | - | - |
| diagnosis | ||
| errmsg | - | - |
| host | - | - |
| ClientToServerSpeed | - | - |
| ServerToClientSpeed | - | - |
| avgrtt | SumRTT / CountRTT | tcpi_rtt? |
| Jitter | MaxRTT – MinRTT | tcpi_rttvar? |
| CurRwinRcvd | CurRwinRcvd | |
| MaxRwinRcvd | MaxRwinRcvd | |
| loss | CongestionSignals / PktsOut | tcpi_lost |
| MinRTT | MinRTT | - |
| MaxRTT | MaxRTT | - |
| Waitsec | (CurRTO * Timeouts) / 1000 |
|
| CurRTO | CurRTO | |
| SACKsRcvd | SACKsRcvd | tcpi_sacked |
| cwndtime | SndLimTimeCwnd / (SndLimTimeRwin + SndLimTimeCwnd + SndLimTimeSender) | |
| rwintime | SndLimTimeRwin / (SndLimTimeRwin + SndLimTimeCwnd + SndLimTimeSender) | |
| optimalRcvrBuffer | MaxRwinRcvd * KILO_BITS |
|
| DupAcksIn | DupAcksIn |
| middlebox | CurMss, WinScaleSent, WinScaleRcvd, SumRTT, CountRTT, MaxRwinRcvd |
|---|---|
| sfw | MaxRTT, MaxRTO |
In server are also test for wireless link and DSL/Cable modem link which is dependent from SndLimTransRwin, SndLimTransCwnd and SndLimTransSender variables (and more).
- C2S throughput test
- S2C throughput test
- Detect S2C & C2S throughput test: Packet queuing
- Simple firewall test (after little change in calculate testTime)
- Connection type (in client)
Rest is depend from Web100/10g specific variables.
