if (sampleDocnosFile != null && fs.exists(new Path(sampleDocnosFile))) {
job.set("Ivory.SampleFile", sampleDocnosFile);
DistributedCache.addCacheFile(new URI(sampleDocnosFile), job);
} else if (sampleSize != -1) {
RetrievalEnvironment env = new RetrievalEnvironment(workDir, fs);
int collectionSize = env.readCollectionDocumentCount();
sampleFreq = collectionSize / (float) sampleSize;
job.setInt("SampleFrequency", (int) sampleFreq);
} else {
throw new RuntimeException("Either provide sample frequency with " +
"option -" + SAMPLESIZE_OPTION+ " or existing sample docnos with option -" + SAMPLEDOCNOS_OPTION);