- tool to perform TCP benchmarking of nameservers
reads DNS queries (by default from standard input) and sends
them out in parallel to a remote nameserver. By default TCP/IP is used, but
optionally, UDP is tried first, which allows for the benchmarking of TCP/IP
The program reports both mean and median numbers for queries per second and UDP
and TCP latency. Each query only counts once, even if it is tried over UDP
first. This effectively means that passing '-u' can lower query rates if many
queries get shunted to TCP.
The input format is one query per line: qname single-space qtype. An example:
When benchmarking extended runs, it may be necessary to enable TIME_WAIT
recycling, as TCP/IP port tuples may otherwise run out. On Linux this is
performed by running:
echo 1 > /proc/sys/net/ipv4/tcp_tw_recycle
The equivalent for IPv6 is not known.
- -f | --file FILENAME
- FILENAME from which to read queries. Defaults to
standard input if unspecified.
- -h | --help
- Provide a helpful message.
- --timeout-msec MSEC
- MSEC milliseconds to wait for an answer.
- -u | --udp-first
- Attempt resolution via UDP first, only do TCP if truncated
answer is received.
- -v | --verbose
- Be wordy on what the program is doing.
- --workers NUM
- Use NUM parallel worker threads.
- IPv4 or IPv6 to test against.
- Port to test against, defaults to 53.
Currently the timeout code does not actually perform non-blocking connects or
writes. So a slow connect or slow writes will still cause low performance and
Median queries per second statistics are reported as 0 for sub-second runs.