NAME

       dbench - Measure disk throughput for simulated netbench run

SYNOPSIS

       dbench [options]numclients
       tbench [options]numclientsserver tbench_srv [options]

DESCRIPTION

       This manual page documents briefly the dbench and tbench benchmarks.  This manual page was
       written for the Debian GNU/Linux distribution because the original program does not have a
       manual page.  However, it has fairly easy to read source code.

       Netbench is a terrible benchmark, but it's an "industry standard" and it's what is used in
       the press to rate windows fileservers like Samba and WindowsNT.
       Given the requirements of running netbench (60 and 150 Windows PCs all  on  switched  fast
       ethernet  and  a  really  grunty server, and some way to nurse all those machines along so
       they will run a very fussy benchmark suite without crashing), these programs were  written
       to open up netbench to the masses.
       Both  dbench  and  tbench  read a load description file called client.txt that was derived
       from a network sniffer dump of a real netbench run. client.txt is about 4MB and  describes
       the  90  thousand  operations  that a netbench client does in a typical netbench run. They
       parse client.txt and use it to produce the same load without having to buy a huge lab.
       dbench produces only the filesystem load. It does all the same  IO  calls  that  the  smbd
       server  in  Samba would produce when confronted with a netbench run. It does no networking
       calls.
       tbench produces only the TCP and process load. It does the same  socket  calls  that  smbd
       would  do under a netbench load. It does no filesystem calls. The idea behind tbench is to
       eliminate smbd from the netbench test, as though the smbd code could  be  made  infinately
       fast.

OPTIONS

       The  dbench  program  takes  a  number,  which  indicates  the  number  of  clients to run
       simultaneously.  It can also take the following options:

       -c client.txt
              Use  this  as  the  full  path  name  of  the  client.txt  file  (the  default   is
              /usr/share/dbench/client.txt).

       -s     Use synchronous file IO on all file operations.

       -t TIME
              set the runtime of the benchmark in seconds (default 600)

       -D DIR set the base directory to run the filesystem operations in

       -x     enable  xattr support, simulating the xattr operations Samba4 would need to perform
              to run the load

       -S     Use synchronous IO for all directory operations (unlink, rmdir, mkdir and rename).
              The tbench program takes a number, which indicates the number  of  clients  to  run
              simultaneously,  and  a  server  name:  tbench_srv should be invoked on that server
              before invoking tbench.  tbench can also take the following options:

       -T option[,...]
              This sets the socket options for the connection to the server.  The options  are  a
              comma-separated  list  of one or more of the following: SO_KEEPALIVE, SO_REUSEADDR,
              SO_BROADCAST,    SO_NODELAY,    SO_LOWDELAY,    SO_THROUGHPUT,    SO_SNDBUF=number,
              SO_RCVBUF=number,  SO_SNDLOWAT=number,  SO_RCVLOWAT=number,  SO_SNDTIMEO=number,and
              SO_RCVTIMEO=number.  See socket(7) for details about these options.
              The tbench_srv can only take one option: -T option[,...]  as documented above.

SEE ALSO

       /usr/share/doc/dbench/README  contains  the  original  README  by  Andrew  Tridgell  which
       accompanies the dbench source.

AUTHOR

       This  manual  page  was originally written by Paul Russell <prussell@alderaan.franken.de>,
       for the Debian GNU/Linux system (but may be used  by  others).  Modified  and  updated  by
       Mattias Nordstrom <nordstrom@realnode.com>.

                                          June 18, 2005                                 DBENCH(1)