From: Alexey Dobriyan <adobriyan@gmail.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: mingo@redhat.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] sched: make nr_running() return "unsigned int"
Date: Thu, 12 Mar 2020 20:09:42 +0300 [thread overview]
Message-ID: <20200312170942.GA7151@avx2> (raw)
In-Reply-To: <20200312104427.GR12561@hirez.programming.kicks-ass.net>
On Thu, Mar 12, 2020 at 11:44:27AM +0100, Peter Zijlstra wrote:
> On Thu, Mar 12, 2020 at 12:06:08AM +0300, Alexey Dobriyan wrote:
> > I don't anyone have been crazy enough to spawn 2^32 threads.
> > It'd require absurd amounts of physical memory.
>
> And we're going to 5 level page-tables because 48 bits physical isn't
> enough. 57 bits of physical is plenty space to spawn that many tasks and
> still have some left over.
>
> Now 32 bit tasks is indeed insane, but memory isn't the problem. The
> actual limit is the pid-space, which is 30 bits.
Indeed, pid space limit is even better!
prev parent reply other threads:[~2020-03-12 17:09 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-11 21:06 [PATCH 1/2] sched: make nr_running() return "unsigned int" Alexey Dobriyan
2020-03-11 21:08 ` [PATCH 2/2] sched: make nr_iowait_cpu() " Alexey Dobriyan
2020-03-12 10:44 ` [PATCH 1/2] sched: make nr_running() " Peter Zijlstra
2020-03-12 17:09 ` Alexey Dobriyan [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200312170942.GA7151@avx2 \
--to=adobriyan@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox