[Gluster-users] Proposal to mark few features as Deprecated / SunSet from Version 5.0

Vijay Bellur vbellur at redhat.com
Wed Mar 20 04:07:46 UTC 2019


I tried this configuration on my local setup and the test passed fine.

Adding the fuse and write-behind maintainers in Gluster to check if they
are aware of any oddities with using mmap & fuse.

Thanks,
Vijay

On Tue, Mar 19, 2019 at 2:21 PM Jim Kinney <jim.kinney at gmail.com> wrote:

> Volume Name: home
> Type: Replicate
> Volume ID: 5367adb1-99fc-44c3-98c4-71f7a41e628a
> Status: Started
> Snapshot Count: 0
> Number of Bricks: 1 x 2 = 2
> Transport-type: tcp,rdma
> Bricks:
> Brick1: bmidata1:/data/glusterfs/home/brick/brick
> Brick2: bmidata2:/data/glusterfs/home/brick/brick
> Options Reconfigured:
> performance.client-io-threads: off
> storage.build-pgfid: on
> cluster.self-heal-daemon: enable
> performance.readdir-ahead: off
> nfs.disable: off
>
>
> There are 11 other volumes and all are similar.
>
>
> On Tue, 2019-03-19 at 13:59 -0700, Vijay Bellur wrote:
>
> Thank you for the reproducer! Can you please let us know the output of
> `gluster volume info`?
>
> Regards,
> Vijay
>
> On Tue, Mar 19, 2019 at 12:53 PM Jim Kinney <jim.kinney at gmail.com> wrote:
>
> This python will fail when writing to a file in a glusterfs fuse mounted
> directory.
>
> import mmap
>
> # write a simple example file
> with open("hello.txt", "wb") as f:
>     f.write("Hello Python!\n")
>
> with open("hello.txt", "r+b") as f:
>     # memory-map the file, size 0 means whole file
>     mm = mmap.mmap(f.fileno(), 0)
>     # read content via standard file methods
>     print mm.readline()  # prints "Hello Python!"
>     # read content via slice notation
>     print mm[:5]  # prints "Hello"
>     # update content using slice notation;
>     # note that new content must have same size
>     mm[6:] = " world!\n"
>     # ... and read again using standard file methods
>     mm.seek(0)
>     print mm.readline()  # prints "Hello  world!"
>     # close the map
>     mm.close()
>
>
>
>
>
>
>
> On Tue, 2019-03-19 at 12:06 -0400, Jim Kinney wrote:
>
> Native mount issue with multiple clients (centos7 glusterfs 3.12).
>
> Seems to hit python 2.7 and 3+. User tries to open file(s) for write on
> long process and system eventually times out.
>
> Switching to NFS stops the error.
>
> No bug notice yet. Too many pans on the fire :-(
>
> On Tue, 2019-03-19 at 18:42 +0530, Amar Tumballi Suryanarayan wrote:
>
> Hi Jim,
>
> On Tue, Mar 19, 2019 at 6:21 PM Jim Kinney <jim.kinney at gmail.com> wrote:
>
>
> Issues with glusterfs fuse mounts cause issues with python file open for
> write. We have to use nfs to avoid this.
>
> Really want to see better back-end tools to facilitate cleaning up of
> glusterfs failures. If system is going to use hard linked ID, need a
> mapping of id to file to fix things. That option is now on for all exports.
> It should be the default If a host is down and users delete files by the
> thousands, gluster _never_ catches up. Finding path names for ids across
> even a 40TB mount, much less the 200+TB one, is a slow process. A network
> outage of 2 minutes and one system didn't get the call to recursively
> delete several dozen directories each with several thousand files.
>
>
>
> Are you talking about some issues in geo-replication module or some other
> application using native mount? Happy to take the discussion forward about
> these issues.
>
> Are there any bugs open on this?
>
> Thanks,
> Amar
>
>
>
>
> nfs
> On March 19, 2019 8:09:01 AM EDT, Hans Henrik Happe <happe at nbi.dk> wrote:
>
> Hi,
>
> Looking into something else I fell over this proposal. Being a shop that
> are going into "Leaving GlusterFS" mode, I thought I would give my two
> cents.
>
> While being partially an HPC shop with a few Lustre filesystems,  we chose
> GlusterFS for an archiving solution (2-3 PB), because we could find files
> in the underlying ZFS filesystems if GlusterFS went sour.
>
> We have used the access to the underlying files plenty, because of the
> continuous instability of GlusterFS'. Meanwhile, Lustre have been almost
> effortless to run and mainly for that reason we are planning to move away
> from GlusterFS.
>
> Reading this proposal kind of underlined that "Leaving GluserFS" is the
> right thing to do. While I never understood why GlusterFS has been in
> feature crazy mode instead of stabilizing mode, taking away crucial
> features I don't get. With RoCE, RDMA is getting mainstream. Quotas are
> very useful, even though the current implementation are not perfect.
> Tiering also makes so much sense, but, for large files, not on a per-file
> level.
>
> To be honest we only use quotas. We got scared of trying out new
> performance features that potentially would open up a new back of issues.
>
> Sorry for being such a buzzkill. I really wanted it to be different.
>
> Cheers,
> Hans Henrik
> On 19/07/2018 08.56, Amar Tumballi wrote:
>
>
> * Hi all, Over last 12 years of Gluster, we have developed many features,
> and continue to support most of it till now. But along the way, we have
> figured out better methods of doing things. Also we are not actively
> maintaining some of these features. We are now thinking of cleaning up some
> of these ‘unsupported’ features, and mark them as ‘SunSet’ (i.e., would be
> totally taken out of codebase in following releases) in next upcoming
> release, v5.0. The release notes will provide options for smoothly
> migrating to the supported configurations. If you are using any of these
> features, do let us know, so that we can help you with ‘migration’.. Also,
> we are happy to guide new developers to work on those components which are
> not actively being maintained by current set of developers. List of
> features hitting sunset: ‘cluster/stripe’ translator: This translator was
> developed very early in the evolution of GlusterFS, and addressed one of
> the very common question of Distributed FS, which is “What happens if one
> of my file is bigger than the available brick. Say, I have 2 TB hard drive,
> exported in glusterfs, my file is 3 TB”. While it solved the purpose, it
> was very hard to handle failure scenarios, and give a real good experience
> to our users with this feature. Over the time, Gluster solved the problem
> with it’s ‘Shard’ feature, which solves the problem in much better way, and
> provides much better solution with existing well supported stack. Hence the
> proposal for Deprecation. If you are using this feature, then do write to
> us, as it needs a proper migration from existing volume to a new full
> supported volume type before you upgrade. ‘storage/bd’ translator: This
> feature got into the code base 5 years back with this patch
> <http://review.gluster.org/4809>[1]. Plan was to use a block device
> directly as a brick, which would help to handle disk-image storage much
> easily in glusterfs. As the feature is not getting more contribution, and
> we are not seeing any user traction on this, would like to propose for
> Deprecation. If you are using the feature, plan to move to a supported
> gluster volume configuration, and have your setup ‘supported’ before
> upgrading to your new gluster version. ‘RDMA’ transport support: Gluster
> started supporting RDMA while ib-verbs was still new, and very high-end
> infra around that time were using Infiniband. Engineers did work with
> Mellanox, and got the technology into GlusterFS for better data migration,
> data copy. While current day kernels support very good speed with IPoIB
> module itself, and there are no more bandwidth for experts in these area to
> maintain the feature, we recommend migrating over to TCP (IP based) network
> for your volume. If you are successfully using RDMA transport, do get in
> touch with us to prioritize the migration plan for your volume. Plan is to
> work on this after the release, so by version 6.0, we will have a cleaner
> transport code, which just needs to support one type. ‘Tiering’ feature
> Gluster’s tiering feature which was planned to be providing an option to
> keep your ‘hot’ data in different location than your cold data, so one can
> get better performance. While we saw some users for the feature, it needs
> much more attention to be completely bug free. At the time, we are not
> having any active maintainers for the feature, and hence suggesting to take
> it out of the ‘supported’ tag. If you are willing to take it up, and
> maintain it, do let us know, and we are happy to assist you. If you are
> already using tiering feature, before upgrading, make sure to do gluster
> volume tier detach all the bricks before upgrading to next release. Also,
> we recommend you to use features like dmcache on your LVM setup to get best
> performance from bricks. ‘Quota’ This is a call out for ‘Quota’ feature, to
> let you all know that it will be ‘no new development’ state. While this
> feature is ‘actively’ in use by many people, the challenges we have in
> accounting mechanisms involved, has made it hard to achieve good
> performance with the feature. Also, the amount of extended attribute
> get/set operations while using the feature is not very ideal. Hence we
> recommend our users to move towards setting quota on backend bricks
> directly (ie, XFS project quota), or to use different volumes for different
> directories etc. As the feature wouldn’t be deprecated immediately, the
> feature doesn’t need a migration plan when you upgrade to newer version,
> but if you are a new user, we wouldn’t recommend setting quota feature. By
> the release dates, we will be publishing our best alternatives guide for
> gluster’s current quota feature. Note that if you want to contribute to the
> feature, we have project quota based issue open
> <https://github.com/gluster/glusterfs/issues/184>[2] Happy to get
> contributions, and help in getting a newer approach to Quota.
> ------------------------------ These are our set of initial features which
> we propose to take out of ‘fully’ supported features. While we are in the
> process of making the user/developer experience of the project much better
> with providing well maintained codebase, we may come up with few more set
> of features which we may possibly consider to move out of support, and
> hence keep watching this space. [1] - http://review.gluster.org/4809
> <http://review.gluster.org/4809> [2] -
> https://github.com/gluster/glusterfs/issues/184
> <https://github.com/gluster/glusterfs/issues/184> Regards, Vijay, Shyam,
> Amar *
>
>
>
> _______________________________________________
>
> Gluster-users mailing list
>
> Gluster-users at gluster.org
>
>
> https://lists.glus
>
>
> --
>
>
> Sent from my Android device with K-9 Mail. All tyopes are thumb related and reflect authenticity.ter.org/mailman/listinfo/gluster-users
>
> <https://lists.gluster.org/mailman/listinfo/gluster-users>
>
>
>
> --
>
>
> James P. Kinney III
>
>
> Every time you stop a school, you will have to build a jail. What you
>
> gain at one end you lose at the other. It's like feeding a dog on his
>
> own tail. It won't fatten the dog.
>
> - Speech 11/23/1900 Mark Twain
>
>
> http://heretothereideas.blogspot.com/
>
> --
>
>
> James P. Kinney III
>
>
> Every time you stop a school, you will have to build a jail. What you
>
> gain at one end you lose at the other. It's like feeding a dog on his
>
> own tail. It won't fatten the dog.
>
> - Speech 11/23/1900 Mark Twain
>
>
> http://heretothereideas.blogspot.com/
>
>
> _______________________________________________
> Gluster-users mailing list
> Gluster-users at gluster.org
> https://lists.gluster.org/mailman/listinfo/gluster-users
>
> --
>
> James P. Kinney III Every time you stop a school, you will have to build a
> jail. What you gain at one end you lose at the other. It's like feeding a
> dog on his own tail. It won't fatten the dog. - Speech 11/23/1900 Mark
> Twain http://heretothereideas.blogspot.com/
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.gluster.org/pipermail/gluster-users/attachments/20190319/ae0516a4/attachment.html>


More information about the Gluster-users mailing list