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From: Miklos Szeredi <miklos@szeredi.hu>
Date: Tue, 4 Jun 2024 09:20:32 +0200
Message-ID: <CAJfpegvYpWuTbKOm1hoySHZocY+ki07EzcXBUX8kZx92T8W6uQ@mail.gmail.com>
Subject: Re: [HELP] FUSE writeback performance bottleneck
To: Dave Chinner <david@fromorbit.com>
Cc: Bernd Schubert <bernd.schubert@fastmail.fm>, Jingbo Xu <jefflexu@linux.alibaba.com>, 
	"linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>, 
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, lege.wang@jaguarmicro.com
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On Tue, 4 Jun 2024 at 00:10, Dave Chinner <david@fromorbit.com> wrote:

> I thought we had PR_SET_IO_FLUSHER for that. Requires
> CAP_SYS_RESOURCES but no other privileges, then the userspace
> server will then always operate in PF_MEMALLOC_NOIO |
> PF_LOCAL_THROTTLE memory allocation context.

There could be any number of services that are being used while
serving a fuse request.  There's no well defined "fuse server
process", as many people seem to think.  Any approach depending on
somehow marking the fuse server as a special entity will fail.

Thanks,
Miklos