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From:   Heiner Litz <hlitz@ucsc.edu>
Date:   Thu, 21 Jan 2021 08:58:58 -0800
Message-ID: <CAJbgVnWxmwfmdgk-e290kcMfhUNAjP9uO2k45rx7R=x8jBdJcw@mail.gmail.com>
Subject: Re: [PATCH] lightnvm: fix memory leak when submit fails
To:     =?UTF-8?Q?Matias_Bj=C3=B8rling?= <mb@lightnvm.io>
Cc:     Jens Axboe <axboe@kernel.dk>, Pan Bian <bianpan2016@163.com>,
        linux-block@vger.kernel.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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I don't think that ZNS supersedes OCSSD. OCSSDs provide much more
flexibility and device control and remain valuable for academia. For
us, PBLK is the most accurate "SSD Emulator" out there that, as
another benefit, enables real-time performance measurements.
That being said, I understand that this may not be a good enough
reason to keep it around, but I wouldn't mind if it stayed for another
while.

On Thu, Jan 21, 2021 at 5:57 AM Matias Bj=C3=B8rling <mb@lightnvm.io> wrote=
:
>
> On 21/01/2021 13.47, Jens Axboe wrote:
> > On 1/21/21 12:22 AM, Pan Bian wrote:
> >> The allocated page is not released if error occurs in
> >> nvm_submit_io_sync_raw(). __free_page() is moved ealier to avoid
> >> possible memory leak issue.
> > Applied, thanks.
> >
> > General question for Matias - is lightnvm maintained anymore at all, or
> > should we remove it? The project seems dead from my pov, and I don't
> > even remember anyone even reviewing fixes from other people.
> >
> Hi Jens,
>
> ZNS has superseded OCSSD/lightnvm. As a result, the hardware and
> software development around OCSSD have also moved on to ZNS. To my
> knowledge, there is not anyone implementing OCSSD1.2/2.0 commercially at
> this point, and what has been deployed in production does not utilize
> the Linux kernel stack.
>
> I do not mind continuing to keep an eye on it, but on the other hand, it
> has served its purpose. It enabled the "Open-Channel SSD architectures"
> of the world to take hold in the market and thereby gained enough
> momentum to be standardized in NVMe as ZNS.
>
> Would you like me to send a PR to remove lightnvm immediately, or should
> we mark it as deprecated for a while before pulling it?
>
> Best, Matias
>
>