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Subject: Re: [RFC] /dev/ioasid uAPI proposal
To:     "Enrico Weigelt, metux IT consult" <lkml@metux.net>,
        Jason Gunthorpe <jgg@nvidia.com>
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        "Alex Williamson (alex.williamson@redhat.com)\"\"" 
        <alex.williamson@redhat.com>, David Woodhouse <dwmw2@infradead.org>
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From:   Jason Wang <jasowang@redhat.com>
Message-ID: <0f9224eb-2158-4769-f709-6e8f56c24bd3@redhat.com>
Date:   Thu, 10 Jun 2021 10:16:17 +0800
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在 2021/6/8 下午6:45, Enrico Weigelt, metux IT consult 写道:
> On 07.06.21 20:01, Jason Gunthorpe wrote:
>> <shrug> it is what it is, select has a fixed size bitmap of FD #s and
>> a hard upper bound on that size as part of the glibc ABI - can't be
>> fixed.
>
> in glibc ABI ? Uuuuh!
>

Note that dealing with select() or try to overcome the limitation via 
epoll() directly via the application is not a good practice (or it's not 
portable).

It's suggested to use building blocks provided by glib, e.g the main 
event loop[1]. That is how Qemu solve the issues of dealing with a lot 
of file descriptors.

Thanks

[1] https://developer.gnome.org/glib/stable/glib-The-Main-Event-Loop.html


>
> --mtx
>