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Date:   Thu, 11 Apr 2019 08:33:13 -0700
From:   Matthew Wilcox <willy@infradead.org>
To:     Suren Baghdasaryan <surenb@google.com>
Cc:     akpm@linux-foundation.org, mhocko@suse.com, rientjes@google.com,
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Subject: Re: [RFC 2/2] signal: extend pidfd_send_signal() to allow expedited
 process killing
Message-ID: <20190411153313.GE22763@bombadil.infradead.org>
References: <20190411014353.113252-1-surenb@google.com>
 <20190411014353.113252-3-surenb@google.com>
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On Wed, Apr 10, 2019 at 06:43:53PM -0700, Suren Baghdasaryan wrote:
> Add new SS_EXPEDITE flag to be used when sending SIGKILL via
> pidfd_send_signal() syscall to allow expedited memory reclaim of the
> victim process. The usage of this flag is currently limited to SIGKILL
> signal and only to privileged users.

What is the downside of doing expedited memory reclaim?  ie why not do it
every time a process is going to die?