Added command-line options to README.

README.md

@@ -63,3 +63,76 @@ remote agents.
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+Command-line Options
+====================
+Usage: mutilate -s server[:port] [options]
+
+"High-performance" memcached benchmarking tool
+
+  -h, --help               Print help and exit
+      --version            Print version and exit
+  -v, --verbose            Verbosity. Repeat for more verbose.
+      --quiet              Disable log messages.
+
+Basic options:
+  -s, --server=STRING      Memcached server hostname[:port].  Repeat to specify
+                             multiple servers.
+  -q, --qps=INT            Target aggregate QPS. 0 = peak QPS.  (default=`0')
+  -t, --time=INT           Maximum time to run (seconds).  (default=`5')
+  -K, --keysize=STRING     Length of memcached keys (distribution).
+                             (default=`30')
+  -V, --valuesize=STRING   Length of memcached values (distribution).
+                             (default=`200')
+  -r, --records=INT        Number of memcached records to use.  If multiple
+                             memcached servers are given, this number is
+                             divided by the number of servers.
+                             (default=`10000')
+  -u, --update=FLOAT       Ratio of set:get commands.  (default=`0.0')
+
+Advanced options:
+  -T, --threads=INT        Number of threads to spawn.  (default=`1')
+  -c, --connections=INT    Connections to establish per server.  (default=`1')
+  -d, --depth=INT          Maximum depth to pipeline requests.  (default=`1')
+  -R, --roundrobin         Assign threads to servers in round-robin fashion.
+                             By default, each thread connects to every server.
+  -i, --iadist=STRING      Inter-arrival distribution (distribution).  Note:
+                             The distribution will automatically be adjusted to
+                             match the QPS given by --qps.
+                             (default=`exponential')
+      --noload             Skip database loading.
+      --loadonly           Load database and then exit.
+  -B, --blocking           Use blocking epoll().  May increase latency.
+  -D, --no_nodelay         Don't use TCP_NODELAY.
+  -w, --warmup=INT         Warmup time before starting measurement.
+  -W, --wait=INT           Time to wait after startup to start measurement.
+  -S, --search=N:X         Search for the QPS where N-order statistic < Xus.
+                             (i.e. --search 95:1000 means find the QPS where
+                             95% of requests are faster than 1000us).
+      --scan=min:max:step  Scan latency across QPS rates from min to max.
+
+Agent-mode options:
+  -A, --agentmode          Run client in agent mode.
+  -a, --agent=host         Enlist remote agent.
+  -l, --lambda_mul=INT     Lambda multiplier.  Increases share of QPS for this
+                             client.  (default=`1')
+
+Some options take a 'distribution' as an argument.
+Distributions are specified by <distribution>[:<param1>[,...]].
+Parameters are not required.  The following distributions are supported:
+
+   [fixed:]<value>              Always generates <value>.
+   uniform:<max>                Uniform distribution between 0 and <max>.
+   normal:<mean>,<sd>           Normal distribution.
+   exponential:<lambda>         Exponential distribution.
+   pareto:<loc>,<scale>,<shape> Generalized Pareto distribution.
+   gev:<loc>,<scale>,<shape>    Generalized Extreme Value distribution.
+
+   To recreate the Facebook "ETC" request stream from [1], the
+   following hard-coded distributions are also provided:
+
+   fb_value   = a hard-coded discrete and GPareto PDF of value sizes
+   fb_key     = "gev:30.7984,8.20449,0.078688", key-size distribution
+   fb_ia      = "pareto:0.0,16.0292,0.154971", inter-arrival time dist.
+
+[1] Berk Atikoglu et al., Workload Analysis of a Large-Scale Key-Value Store,
+    SIGMETRICS 2012