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- TTCP(1) USER COMMANDS TTCP(1)
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- NAME
- ttcp - test TCP and UDP performance
-
- SYNOPSIS
- ttcp -t [-u] [-s] [-p _p_o_r_t] [-l _b_u_f_l_e_n] [-b _s_i_z_e]
- [-n _n_u_m_b_u_f_s] [-A _a_l_i_g_n] [-O _o_f_f_s_e_t] [-f _f_o_r_m_a_t] [-D] [-v]
- host [<in]
- ttcp -r [-u] [-s] [-p _p_o_r_t] [-l _b_u_f_l_e_n] [-b _s_i_z_e] [-A _a_l_i_g_n]
- [-O _o_f_f_s_e_t] [-f _f_o_r_m_a_t] [-B] [-T] [-v] [>out]
-
- DESCRIPTION
- _T_t_c_p times the transmission and reception of data between
- two systems using the UDP or TCP protocols. It differs from
- common ``blast'' tests, which tend to measure the remote
- _i_n_e_t_d as much as the network performance, and which usually
- do not allow measurements at the remote end of a UDP
- transmission.
-
- For testing, the transmitter should be started with -t and
- -s after the receiver has been started with -r and -s.
- Tests lasting at least tens of seconds should be used to
- obtain accurate measurements. Graphical presentations of
- throughput versus buffer size for buffers ranging from tens
- of bytes to several ``pages'' can illuminate bottlenecks.
-
- _T_t_c_p can also be used as a ``network pipe'' for moving
- directory hierarchies between systems when routing problems
- exist or when the use of other mechanisms is undesirable.
- For example, on the destination machine, use: ttcp -r -B |
- tar xvpf -
-
- and on the source machine: tar cf - directory | ttcp -t
- dest_machine
-
- Additional intermediate machines can be included by: ttcp -r
- | ttcp -t next_machine
-
- OPTIONS
- -t Transmit mode.
-
- -r Receive mode.
-
- -u Use UDP instead of TCP.
-
- -s If transmitting, source a data pattern to network;
- if receiving, sink (discard) the data. Without
- the -s option, the default is to transmit data
- from _s_t_d_i_n or print the received data to _s_t_d_o_u_t.
-
- -l _l_e_n_g_t_h Length of buffers in bytes (default 8192). For
- UDP, this value is the number of data bytes in
- each packet. The system limits the maximum UDP
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- Sun Release 4.1 Last change: local 1
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- TTCP(1) USER COMMANDS TTCP(1)
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-
-
- packet length. This limit can be changed with the
- -b option.
-
- -b _s_i_z_e Set size of socket buffer. The default varies
- from system to system. This parameter affects the
- maximum UDP packet length. It may not be possible
- to set this parameter on some systems (for exam-
- ple, 4.2BSD).
-
- -n _n_u_m_b_u_f_s
- Number of source buffers transmitted (default
- 2048).
-
- -p _p_o_r_t Port number to send to or listen on (default
- 2000). On some systems, this port may be allo-
- cated to another network daemon.
-
- -D If transmitting using TCP, do not buffer data when
- sending (sets the TCP_NODELAY socket option). It
- may not be possible to set this parameter on some
- systems (for example, 4.2BSD).
-
- -B When receiving data, output only full blocks,
- using the block size specified by -l. This option
- is useful for programs, such as _t_a_r(1), that
- require complete blocks.
-
- -A _a_l_i_g_n Align the start of buffers to this modulus
- (default 16384).
-
- -O _o_f_f_s_e_t Align the start of buffers to this offset (default
- 0). For example, ``-A8192 -O1'' causes buffers to
- start at the second byte of an 8192-byte page.
-
- -f _f_o_r_m_a_t Specify, using one of the following characters,
- the format of the throughput rates as kilobits/sec
- ('k'), kilobytes/sec ('K'), megabits/sec ('m'),
- megabytes/sec ('M'), gigabits/sec ('g'), or
- gigabytes/sec ('G'). The default is 'K'.
-
- -T ``Touch'' the data as they are read in order to
- measure cache effects.
-
- -v Verbose: print more statistics.
-
- -d Debug: set the SO_DEBUG socket option.
-
- SEE ALSO
- ping(1M), traceroute(1M), netsnoop(1M)
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- Sun Release 4.1 Last change: local 2
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