Things spun out of GFPS API work
Mar. 25th, 2014 09:50 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
sawylI've discovered a couple of elegant spin-offs from my current work on GPFS. Playing around with the pool structures and calls in the API, I've found it to be much faster than
I've also realised that if I combine a couple of other calls, I can both identify the fileset that owns a particular directory and pull out the three levels of quota — user, group, fileset — for it. This makes it trivially easy to summarise all the limits imposed on a particular user in a way that indicates both their current level of consumption, how much they have left, and the level at which the resource is being constrained.
And best of all, the code to do all this can be wrapped up in a handful of Cython calls. OK so the fileset identification code seems to need an inode scan, which seems to mean it can't be run as a normal user, and I haven't yet found a way to dump out a complete list of filesets defined within the file system — although this information must be available be
mmdf, largely because the latter goes out to each NSD and queries it for its usage information — something that's not of much interest if you just want to know whether the pools are full or not.I've also realised that if I combine a couple of other calls, I can both identify the fileset that owns a particular directory and pull out the three levels of quota — user, group, fileset — for it. This makes it trivially easy to summarise all the limits imposed on a particular user in a way that indicates both their current level of consumption, how much they have left, and the level at which the resource is being constrained.
And best of all, the code to do all this can be wrapped up in a handful of Cython calls. OK so the fileset identification code seems to need an inode scan, which seems to mean it can't be run as a normal user, and I haven't yet found a way to dump out a complete list of filesets defined within the file system — although this information must be available be
mmlsfileset and mmrepquota can do it — but it's an extremely handy thing to get out of something originally intended for a completely different purpose...
