protected byte[] getKeyBytes(final long index) {
        final byte[] ks = new byte[8];
        Bits.putLong(ks, 0, index);
        return ks;
    }
Execute write batch template.

@param template write batch template
jraft-core/src/main/java/com/alipay/sofa/jraft/storage/impl/RocksDBLogStorage.java