Kernel messages when running elasticsearch

Hi there, ever since I started running ES on one of our machines, I'm
seeing the following kernel messages quite often. Then I started a second
machine running as full replica of the first machine (all indexing requests
are still sent to the first machine, averages between 10-20 documents per
second), but I don't see such kernel messages at all on the second machine,
and the first machine is still having these kernel messages. Are these
messages alarming? Or can I just ignore it?

kjournald(11352): WRITE block 641601792 on sdc
kjournald(11352): WRITE block 641607008 on sdc
kjournald(11352): WRITE block 641607336 on sdc
kjournald(11352): WRITE block 641638048 on sdc
kjournald(11352): WRITE block 641638688 on sdc
java(13251): dirtied inode 14845373 (_9hvb.fnm) on sdc
java(13251): dirtied inode 14846225 (_9hto.fdx) on sdc
java(13251): dirtied inode 14846219 (_9hto.fdt) on sdc
java(13251): dirtied inode 14845434 (_9hvb.fdt) on sdc
java(13251): dirtied inode 14845767 (_9hvb.fdx) on sdc
java(13251): dirtied inode 14846234 (_9hto.tis) on sdc
java(13251): dirtied inode 14846237 (_9hto.frq) on sdc
java(13251): dirtied inode 14846238 (_9hto.prx) on sdc
java(13251): dirtied inode 14845772 (_9hvb.tis) on sdc
java(13251): dirtied inode 14845986 (_9hvb.prx) on sdc
java(13251): dirtied inode 14845984 (_9hvb.frq) on sdc
java(21290): READ block 260237280 on sdc
java(21290): READ block 260262040 on sdc
java(21290): READ block 260273408 on sdc
java(21290): READ block 260262968 on sdc
java(21290): READ block 260265216 on sdc