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Subject: Re: nbd: please don't spawn 16 threads when nbd is not even in use
To:     Pavel Machek <pavel@ucw.cz>, Yu Kuai <yukuai1@huaweicloud.com>
Cc:     Eric Blake <eblake@redhat.com>,
        kernel list <linux-kernel@vger.kernel.org>,
        josef@toxicpanda.com, linux-block@vger.kernel.org,
        nbd@other.debian.org, "yukuai (C)" <yukuai3@huawei.com>
References: <Y3y4+QqOlF00X9ET@duo.ucw.cz>
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 <ccee0ff5-309c-b430-09c7-8d2081c9981d@huaweicloud.com>
 <Y39CFnRwNGBGIsCH@duo.ucw.cz>
From:   Yu Kuai <yukuai1@huaweicloud.com>
Message-ID: <f07f496d-3bf7-eb84-eb90-df2d43c5c01b@huaweicloud.com>
Date:   Thu, 24 Nov 2022 19:17:05 +0800
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Hi,

在 2022/11/24 18:06, Pavel Machek 写道:
> 
> Can we get that reverted?
> 
> That is rather obscure bug (how many GFP_KERNEL failures do you
> normally see?) and it costs, dunno, 100KB? of unswappable memory.
> 

No, I don't think that can be reverted. Introduce a BUG just to save
some memory sounds insane.

If you really want to do this. I think the right thing to do is to move
the allocation of recv_workq back to start device, and also fix the
problem properly.

Thanks,
Kuai
> Best regards,
> 								Pavel
>