title: where are extended attributes stored?
body: <p>This is a simple question but I've done some research and can't find any answers... So does anyone know if when we define extended attributes through xattr, those attributes are stored within - as a part of - the file'contents(in the biggining, in the end?), or if the inode has a special region to store these?</p>
  
  <p>And by the way, i've read that in ext4 "each extended attribute is limited to a filesystem block (e.g. 4 KiB)". I can't tell if this is enough if I wanted to store 7 extended attributes to each file in the file system. Is this reallistic?</p>
  
  <p>My last question is if those extended attributes are portable in the sense that if the files move to other machines with different file systems what happens to this attributes?</p>