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From: Guenter Roeck <linux@roeck-us.net>
To: Heinrich Schuchardt <xypron.glpk@gmx.de>,
	Andrew Morton <akpm@linux-foundation.org>
Cc: Aaron Tomlin <atomlin@redhat.com>,
	Andy Lutomirski <luto@amacapital.net>,
	Davidlohr Bueso <dave@stgolabs.net>,
	David Rientjes <rientjes@google.com>,
	"David S. Miller" <davem@davemloft.net>,
	Fabian Frederick <fabf@skynet.be>,
	"H. Peter Anvin" <hpa@zytor.com>, Ingo Molnar <mingo@kernel.org>,
	Jens Axboe <axboe@fb.com>, Joe Perches <joe@perches.com>,
	Johannes Weiner <hannes@cmpxchg.org>,
	Jonathan Corbet <corbet@lwn.net>,
	Kees Cook <keescook@chromium.org>,
	Michael Marineau <mike@marineau.org>,
	Oleg Nesterov <oleg@redhat.com>,
	"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Prarit Bhargava <prarit@redhat.com>,
	Rik van Riel <riel@redhat.com>,
	Rusty Russell <rusty@rustcorp.com.au>,
	Steven Rostedt <rostedt@goodmis.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Vladimir Davydov <vdavydov@parallels.com>,
	linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org
Subject: Re: [PATCH 4/4 v6] Doc/sysctl/kernel.txt: document threads-max
Date: Sun, 15 Mar 2015 09:30:54 -0700	[thread overview]
Message-ID: <5505B3BE.1020800@roeck-us.net> (raw)
In-Reply-To: <1426436018-5159-5-git-send-email-xypron.glpk@gmx.de>

On 03/15/2015 09:13 AM, Heinrich Schuchardt wrote:
> File /proc/sys/kernel/threads-max controls the maximum number
> of threads that can be created using fork().
>
> Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
> ---
>   Documentation/sysctl/kernel.txt | 21 +++++++++++++++++++++
>   1 file changed, 21 insertions(+)
>
> diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt
> index 75511ef..40f9c90 100644
> --- a/Documentation/sysctl/kernel.txt
> +++ b/Documentation/sysctl/kernel.txt
> @@ -846,6 +846,27 @@ can be ORed together:
>
>   ==============================================================
>
> +threads-max
> +
> +This value controls the maximum number of threads that can be created
> +using fork().
> +
> +During initialization the kernel sets this value such that even if the
> +maximum number of threads is created, the thread structures occupy only
> +a part (1/8th) of the available RAM pages.
> +
> +The minimum value that can be written to threads-max is 20.
> +The maximum vlaue that can be written to threads-max is given by the

value

> +constant FUTEX_TID_MASK (0x3fffffff).
> +If a value outside of this range is written to threads-max an error
> +EINVAL occurs.
> +
> +The value written is checked against the available RAM pages. If the
> +thread structures would occupy too much (more than 1/8th) of the
> +available RAM pages threads-max is reduced accordingly.
> +
> +==============================================================
> +
>   unknown_nmi_panic:
>
>   The value in this file affects behavior of handling NMI. When the
>


  reply	other threads:[~2015-03-15 16:31 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-03-15 16:13 [PATCH 0/4 v6] max_threadx handling Heinrich Schuchardt
2015-03-15 16:13 ` [PATCH 1/4 v6] kernel/fork.c: new function for max_threads Heinrich Schuchardt
2015-03-15 16:13 ` [PATCH 2/4 v6] kernel/fork.c: avoid division by zero Heinrich Schuchardt
2015-03-16  7:41   ` Ingo Molnar
2015-03-17 19:19     ` Heinrich Schuchardt
2015-03-18 16:49       ` Ingo Molnar
2015-03-18 17:06         ` Oleg Nesterov
2015-03-25 12:25           ` Ingo Molnar
2015-03-15 16:13 ` [PATCH 3/4 v6] kernel/sysctl.c: threads-max observe limits Heinrich Schuchardt
2015-03-15 16:13 ` [PATCH 4/4 v6] Doc/sysctl/kernel.txt: document threads-max Heinrich Schuchardt
2015-03-15 16:30   ` Guenter Roeck [this message]
2015-03-25 18:59 ` [PATCH 0/4 v6] max_threadx handling Heinrich Schuchardt

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