linux-kernel - Re: [PATCH 4/4 v6] Doc/sysctl/kernel.txt: document threads-max

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <5505B3BE.1020800@roeck-us.net>
Date:	Sun, 15 Mar 2015 09:30:54 -0700
From:	Guenter Roeck <linux@...ck-us.net>
To:	Heinrich Schuchardt <xypron.glpk@....de>,
	Andrew Morton <akpm@...ux-foundation.org>
CC:	Aaron Tomlin <atomlin@...hat.com>,
	Andy Lutomirski <luto@...capital.net>,
	Davidlohr Bueso <dave@...olabs.net>,
	David Rientjes <rientjes@...gle.com>,
	"David S. Miller" <davem@...emloft.net>,
	Fabian Frederick <fabf@...net.be>,
	"H. Peter Anvin" <hpa@...or.com>, Ingo Molnar <mingo@...nel.org>,
	Jens Axboe <axboe@...com>, Joe Perches <joe@...ches.com>,
	Johannes Weiner <hannes@...xchg.org>,
	Jonathan Corbet <corbet@....net>,
	Kees Cook <keescook@...omium.org>,
	Michael Marineau <mike@...ineau.org>,
	Oleg Nesterov <oleg@...hat.com>,
	"Paul E. McKenney" <paulmck@...ux.vnet.ibm.com>,
	Peter Zijlstra <peterz@...radead.org>,
	Prarit Bhargava <prarit@...hat.com>,
	Rik van Riel <riel@...hat.com>,
	Rusty Russell <rusty@...tcorp.com.au>,
	Steven Rostedt <rostedt@...dmis.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	Vladimir Davydov <vdavydov@...allels.com>,
	linux-kernel@...r.kernel.org, linux-doc@...r.kernel.org
Subject: Re: [PATCH 4/4 v6] Doc/sysctl/kernel.txt: document threads-max

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@....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
>

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/