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Message-ID: <ce886be9-41d3-47b6-82e9-57d8f1f3421f@linux.alibaba.com>
Date: Tue, 28 May 2024 12:02:46 +0800
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Subject: Re: [RFC 0/2] fuse: introduce fuse server recovery mechanism
To: Jingbo Xu <jefflexu@linux.alibaba.com>, Miklos Szeredi
 <miklos@szeredi.hu>, Christian Brauner <brauner@kernel.org>
Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
 winters.zc@antgroup.com
References: <20240524064030.4944-1-jefflexu@linux.alibaba.com>
 <CAJfpeguS3PBi-rNtnR2KH1ZS1t4s2HnB_pt4UvnN1orvkhpMew@mail.gmail.com>
 <858d23ec-ea81-45cb-9629-ace5d6c2f6d9@linux.alibaba.com>
 <6a3c3035-b4c4-41d9-a7b0-65f72f479571@linux.alibaba.com>
From: Gao Xiang <hsiangkao@linux.alibaba.com>
In-Reply-To: <6a3c3035-b4c4-41d9-a7b0-65f72f479571@linux.alibaba.com>
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On 2024/5/28 11:08, Jingbo Xu wrote:
> 
> 
> On 5/28/24 10:45 AM, Jingbo Xu wrote:
>>
>>
>> On 5/27/24 11:16 PM, Miklos Szeredi wrote:
>>> On Fri, 24 May 2024 at 08:40, Jingbo Xu <jefflexu@linux.alibaba.com> wrote:
>>>
>>>> 3. I don't know if a kernel based recovery mechanism is welcome on the
>>>> community side.  Any comment is welcome.  Thanks!
>>>
>>> I'd prefer something external to fuse.
>>
>> Okay, understood.
>>
>>>
>>> Maybe a kernel based fdstore (lifetime connected to that of the
>>> container) would a useful service more generally?
>>
>> Yeah I indeed had considered this, but I'm afraid VFS guys would be
>> concerned about why we do this on kernel side rather than in user space.

Just from my own perspective, even if it's in FUSE, the concern is
almost the same.

I wonder if on-demand cachefiles can keep fds too in the future
(thus e.g. daemonless feature could even be implemented entirely
with kernel fdstore) but it still has the same concern or it's
a source of duplication.

Thanks,
Gao Xiang

>>
>> I'm not sure what the VFS guys think about this and if the kernel side
>> shall care about this.
>>
> 
> There was an RFC for kernel-side fdstore [1], though it's also
> implemented upon FUSE.
> 
> [1]
> https://lore.kernel.org/all/CA+a=Yy5rnqLqH2iR-ZY6AUkNJy48mroVV3Exmhmt-pfTi82kXA@mail.gmail.com/T/
> 
> 
>