Core Properties

Core YCSB properties

All workload files can specify the following properties:

• workload: workload class to use (e.g. com.yahoo.ycsb.workloads.CoreWorkload)
• recordcount: the number of records in the dataset at the start of the workload. used when loading for all workloads. (default: 1000)
  
• operationcount: the number of operations to perform in the workload (default: 1000)
  
• db: database class to use. Alternatively this may be specified on the command line. (default: com.yahoo.ycsb.BasicDB)
• exporter: measurements exporter class to use (default: com.yahoo.ycsb.measurements.exporter.TextMeasurementsExporter)
• exportfile: path to a file where output should be written instead of to stdout (default: undefined/write to stdout)
• threadcount: number of YCSB client threads. Alternatively this may be specified on the command line. (default: 1)
• measurementtype: supported measurement types are hdrhistogram, histogram and timeseries (default: hdrhistogram)

Core workload package properties

The property files used with the core workload generator can specify values for the following properties:

• fieldcount: the number of fields in a record (default: 10)
  
• fieldlength: the size of each field (default: 100)
  
• minfieldlength: the minimum size of each field (default: 1)
  
• readallfields: should reads read all fields (true) or just one (false) (default: true)
  
• writeallfields: should updates and read/modify/writes update all fields (true) or just one (false) (default: false)
  
• readproportion: what proportion of operations should be reads (default: 0.95)
  
• updateproportion: what proportion of operations should be updates (default: 0.05)
  
• insertproportion: what proportion of operations should be inserts (default: 0)
  
• scanproportion: what proportion of operations should be scans (default: 0)
  
• readmodifywriteproportion: what proportion of operations should be read a record, modify it, write it back (default: 0)
  
• requestdistribution: what distribution should be used to select the records to operate on – uniform, zipfian, hotspot, sequential, exponential or latest (default: uniform)
  
• minscanlength: for scans, what is the minimum number of records to scan (default: 1)
  
• maxscanlength: for scans, what is the maximum number of records to scan (default: 1000)
  
• scanlengthdistribution: for scans, what distribution should be used to choose the number of records to scan, for each scan, between 1 and maxscanlength (default: uniform)
  
• insertstart: for parallel loads and runs, defines the starting record for this YCSB instance (default: 0)
  
• insertcount: for parallel loads and runs, defines the number of records for this YCSB instance (default: recordcount)
  
• zeropadding: for generating a record sequence compatible with string sort order by 0 padding the record number. Controls the number of 0s to use for padding. (default: 1)
  For example for row 5, with zeropadding=1 you get ‘user5’ key and with zeropading=8 you get ‘user00000005’ key. In order to see its impact, zeropadding needs to be bigger than number of digits in the record number.
  
• insertorder: should records be inserted in order by key (“ordered”), or in hashed order (“hashed”) (default: hashed)
  
• fieldnameprefix: what should be a prefix for field names, the shorter may decrease the required storage size (default: “field”)

Measurement properties

These properties apply to each measurement type:

hdrhistogram

• hdrhistogram.percentiles: comma seperated list of percentile values to be calculated for each measurement (default: 95,99)
• hdrhistogram.fileoutput=true|false This option will enable periodical writes of the interval histogram into an output file. The path can be set through the ‘hdrhistogram.output.path’ property.

histogram

• histogram.buckets: number of buckets for histogram output (default: 1000)

timeseries

• timeseries.granularity: granularity for the timeseries output (default: 1000)