private void logProgress(final long blockNum) {
    final long elapseMicros = segmentTimer.elapsed(TimeUnit.MICROSECONDS);
    //noinspection PlaceholderCountMatchesArgumentCount
    LOG.info(
        "Import at block {} / {} gas {} micros / Mgps {} segment {} cumulative",
        blockNum,
        segmentGas,
        elapseMicros,
        segmentGas / (double) elapseMicros,
        cumulativeGas / (double) cumulativeTimer.elapsed(TimeUnit.MICROSECONDS));
    segmentGas = 0;
    segmentTimer.reset();
  }
Import blockchain.

@param blocks the blocks
@param besuController the besu controller
@param skipPowValidation the skip pow validation
@param startBlock the start block
@param endBlock the end block
@return the rlp block importer - import result
@throws IOException the io exception
app/src/main/java/org/hyperledger/besu/chainimport/RlpBlockImporter.java