Re: [Lsf-pc] [LSF/MM TOPIC] [LSF/MM ATTEND] FS Management Interfaces
Hi, On 10/01/17 10:14, Jan Kara wrote: Hi, On Tue 10-01-17 09:44:59, Steven Whitehouse wrote: I had originally thought about calling the proposal "kernel/userland interface", however that seemed a bit vague and management interfaces seems like a better title since it is I hope a bit clearer of the kind of thing that I'm thinking about in this case. There are a number of possible sub-topics and I hope that I might find a few more before LSF too. One is that of space management (we have statfs, but currently no notifications for thresholds crossed etc., so everything is polled. That is ok sometimes, but statfs can be expensive in the case of distributed filesystems, if 100% accurate. We could just have ENOSPC notifications for 100% full, or something more generic), another is state transitions (is the fs running normally, or has it gone read only/withdrawn/etc due to I/O errors?) and a further topic would be working towards a common interface for fs statistics (at the moment each fs defines their own interface). One potential implementation, at least for the first two sub-topics, would be to use something along the lines of the quota netlink interface, but since few ideas survive first contact with the community at large, I'm throwing this out for further discussion and feedback on whether this approach is considered the right way to go. Assuming the topic is accepted, my intention would be to gather together some additional sub-topics relating to fs management to go along with those I mentioned above, and I'd be very interested to hear of any other issues that could be usefully added to the list for discussion. So this topic came up last year and probably the year before as well (heh, I can even find some patches from 2011 [1]). I think the latest attempt at what you suggest was here [2]. So clearly there's some interest in these interfaces but not enough to actually drive anything to completion. So for this topic to be useful, I think you need to go at least through the patches in [2] and comments to them and have a concrete proposal that can be discussed and some commitment (not necessarily from yourself) that someone is going to devote time to implement it. Because generally nobody seems to be opposed to the abstract idea but once it gets to the implementation details, it is non-trivial to get some wider agreement (statx anybody? ;)). Honza [1] https://lkml.org/lkml/2011/8/18/170 [2] https://lkml.org/lkml/2015/6/16/456 Yes, statx is something else I'd like to see progress too :-) Going back to this topic though, I agree wrt having a concrete proposal, and I'll try and have something ready for LSF, we have a few weeks in hand. I'll collect up the details of the previous efforts (including Lukas' suggestion) and see how far we can get in the mean time, Steve. -- To unsubscribe from this list: send the line "unsubscribe linux-block" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
[LSF/MM TOPIC] [LSF/MM ATTEND] FS Management Interfaces
Hi, This is a request both to attend LSF/MM and also a topic proposal. The last couple of years I've proposed a topic of the block/fs interface. I'm happy to do that again, if there is consensus that this would be useful, however this time I thought that I'd propose something a bit different. I had originally thought about calling the proposal "kernel/userland interface", however that seemed a bit vague and management interfaces seems like a better title since it is I hope a bit clearer of the kind of thing that I'm thinking about in this case. There are a number of possible sub-topics and I hope that I might find a few more before LSF too. One is that of space management (we have statfs, but currently no notifications for thresholds crossed etc., so everything is polled. That is ok sometimes, but statfs can be expensive in the case of distributed filesystems, if 100% accurate. We could just have ENOSPC notifications for 100% full, or something more generic), another is state transitions (is the fs running normally, or has it gone read only/withdrawn/etc due to I/O errors?) and a further topic would be working towards a common interface for fs statistics (at the moment each fs defines their own interface). One potential implementation, at least for the first two sub-topics, would be to use something along the lines of the quota netlink interface, but since few ideas survive first contact with the community at large, I'm throwing this out for further discussion and feedback on whether this approach is considered the right way to go. Assuming the topic is accepted, my intention would be to gather together some additional sub-topics relating to fs management to go along with those I mentioned above, and I'd be very interested to hear of any other issues that could be usefully added to the list for discussion. My interest in other topics is fairly wide... I'm, as usual, interested in all filesystem related topics and a good number of block device and mm topics too. Anything relating to vfs, xfs, ext*, btrfs, gfs2, overlayfs, NFS/CIFS, and technologies such as copy-offload, DAX, reflink, RDMA, NVMe(F), etc., Steve. -- To unsubscribe from this list: send the line "unsubscribe linux-block" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
