From: "Chandy, John" <john.chandy@uconn.edu>
To: Boaz Harrosh <ooo@electrozaur.com>
CC: Christoph Hellwig <hch@lst.de>,
        "martin.petersen@oracle.com" <martin.petersen@oracle.com>,
        "trond.myklebust@primarydata.com" <trond.myklebust@primarydata.com>,
        "axboe@kernel.dk" <axboe@kernel.dk>,
        "osd-dev@open-osd.org" <osd-dev@open-osd.org>,
        "linux-nfs@vger.kernel.org" <linux-nfs@vger.kernel.org>,
        "linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
        "linux-block@vger.kernel.org" <linux-block@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: RFC: drop the T10 OSD code and its users
Thread-Topic: RFC: drop the T10 OSD code and its users
Thread-Index: AQHSs6YsHqZr9SDxRk+z8oW3qq0qTKHLWRkAgAAL0gA=
Date: Tue, 18 Apr 2017 17:06:25 +0000
Message-ID: <1F41407D-B78F-46E3-8FBE-90A5B1E5C3DE@uconn.edu>
References: <20170412160109.10598-1-hch@lst.de>
 <13c543db-dd38-1825-a58d-b4dff99e5f3c@electrozaur.com>
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As one of those academics that Boaz was talking about, we do use the OSD driver for various research projects including support for OSD in parallel file systems like OrangeFS and Lustre.

John.

> On Apr 18, 2017, at 12:24 PM, Boaz Harrosh <ooo@electrozaur.com> wrote:
> 
> On 04/12/2017 07:01 PM, Christoph Hellwig wrote:
> 
> Hi Sir Christoph
> 
>> The only real user of the T10 OSD protocol, the pNFS object layout
>> driver never went to the point of having shipping products, and the
>> other two users (osdblk and exofs) were simple example of it's usage.
>> 
> 
> I understand why osdblk might be a pain, and was broken from day one, and
> should by all means go away ASAP.
> 
> But exofs should not be bothering anyone, and as far as I know does
> not use any special API's except the osd_uld code of course.
> 
>> The code has been mostly unmaintained for years and is getting in the
>> way of block / SCSI changes, so I think it's finally time to drop it.
>> 
> 
> Please tell me what are those changes you are talking about? I might be
> able to help in conversion. I guess you mean osd_uld and the Upper SCSI API.
> Just point me at a tree where osd_uld is broken, and perhaps with a little
> guidance from you I can do a satisfactory conversion.
> 
> Is true that no new code went in for a long while, but I still from time
> to time run a setup and test that the all stack, like iscsi-bidi and so on still
> works.
> 
> That said, yes only a stand alone exofs was tested for a long time, a full
> pnfs setup is missing any supporting server. So Yes I admit that pnfs-obj is
> getting very rotten. And is most probably broken, on the pnfs side of things.
> [Which I admit makes my little plea kind of mute ;-) ]
> 
> Every once in a while I get emails from Students basing all kind of interesting
> experiments on top of the exofs and object base storage. So for the sake of academics
> and for the sake of a true bidi-stack testing, might we want to evaluate what is the
> up coming cost, and what is a minimum set we are willing to keep?
> 
> Please advise?
> 
> thanks
> Boaz
> 
>> These patches are against Jens' block for-next tree as that already
>> has various modifications of the SCSI code.
>> 
> 
> --
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