[Gluster-devel] Order of server-side xlators

Xavier Hernandez xhernandez at datalab.es
Mon Jan 12 13:02:55 UTC 2015


Hi,

looking at the server-side xlator stack created on a generic volume with 
quota enabled, I see the following xlators:

     posix
     changelog
     access-control
     locks
     io-threads
     barrier
     index
     marker
     quota
     io-stats
     server

The question is why access-control and quota are in this relative order. 
It would seem more logical to me to be in the reverse order because if 
an operation is not permitted, it's irrelevant if there is enough quota 
to do it or not: gluster should return EPERM or EACCES instead of EDQUOT.

Also, index and marker can operate on requests that can be later denied 
by access-control, having to undo the work done in that case. Wouldn't 
it be better to use index and marker after having validated all 
permissions of the request ?

I'm not very familiarized with these xlators, so maybe I'm missing an 
important detail.

Thanks,

Xavi


More information about the Gluster-devel mailing list