JRobin学习---JRobin的基本语法

Create new RRD file

rrd:

rrdtool create test.rrd --step 300 \
DS:input:COUNTER:600:0:U \
DS:output:COUNTER:600:0:U \
RRA:AVERAGE:0.5:1:600 \
RRA:AVERAGE:0.5:6:700 \
RRA:AVERAGE:0.5:24:797 \
RRA:AVERAGE:0.5:288:775 \
RRA:MAX:0.5:1:600 \
RRA:MAX:0.5:6:700 \
RRA:MAX:0.5:24:797 \
RRA:MAX:0.5:288:775

jrobin

// create new RRD definition
RrdDef def = new RrdDef("test.rrd", 300);
def.addDatasource("input", "COUNTER", 600, 0, Double.NaN);
def.addDatasource("output", "COUNTER", 600, 0, Double.NaN);
def.addArchive("AVERAGE", 0.5, 1, 600);
def.addArchive("AVERAGE", 0.5, 6, 700);
def.addArchive("AVERAGE", 0.5, 24, 797);
def.addArchive("AVERAGE", 0.5, 288, 775);
def.addArchive("MAX", 0.5, 1, 600);
def.addArchive("MAX", 0.5, 6, 700);
def.addArchive("MAX", 0.5, 24, 797);
def.addArchive("MAX", 0.5, 288, 775);

// RRD file definition is completed, create the database!
RrdDb rrd = new RrdDb(def);
// by this point, file "test.rrd" can be found on your disk

Update RRD files

rrd:

rrdtool update test.rrd timestamp:inputValue:outputValue

jrobin

// open the file
RrdDb rrd = new RrdDb("test.rrd");

// obtain values for timestamp, inputValue and outputValue somehow
long timestamp = ...; // without milliseconds, rounded to the neares second (see notes)
double inputValue = ...;
double outputValue = ...;

// create new, empty data sample using RRD file reference:
Sample sample = rrd.createSample(timestamp);

// put datasource values in your sample
sample.setValue("input", inputValue); // or: sample.setValue(0, inputValue)
sample.setValue("output", outputValue); // or: sample.setValue(1, outputValue);

// update rrd file
sample.update();