From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael Kerrisk (man-pages)" Subject: Re: [PATCH] proc.5: details for threads-max Date: Fri, 11 Sep 2015 13:30:20 +0200 Message-ID: <55F2BB4C.9040908@gmail.com> References: <1440538574-14549-1-git-send-email-xypron.glpk@gmx.de> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1440538574-14549-1-git-send-email-xypron.glpk-Mmb7MZpHnFY@public.gmane.org> Sender: linux-man-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Heinrich Schuchardt Cc: mtk.manpages-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, linux-man-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-man@vger.kernel.org Hello Heinrich, On 08/25/2015 11:36 PM, Heinrich Schuchardt wrote: > Add detail information for threads-max. > The checks for minimum and maximum values exist since kernel 4.1. > https://lkml.org/lkml/2015/3/15/96 > > Signed-off-by: Heinrich Schuchardt > --- > man5/proc.5 | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > > diff --git a/man5/proc.5 b/man5/proc.5 > index bb648d4..83f30af 100644 > --- a/man5/proc.5 > +++ b/man5/proc.5 > @@ -4265,8 +4265,22 @@ this is the fifth kernel built from this source base and the > date following it indicates the time the kernel was built. > .TP > .IR /proc/sys/kernel/threads-max " (since Linux 2.3.11)" > +.\" The following is based on Documentation/sysctl/kernel.txt > This file specifies the system-wide limit on the number of > threads (tasks) that can be created on the system. > + > +The minimum value that can be written to threads-max is 20. > +The maximum value that can be written to threads-max is given by the > +constant > +.B FUTEX_TID_MASK > +(0x3fffffff). > +If a value outside of this range is written to threads-max an error > +.B 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. > .TP > .IR /proc/sys/kernel/zero-paged " (PowerPC only) " > This file Thanks. Applied. It's also important to not the kernel version that added these range checks, I think. So I've added that info also. Cheers, Michael -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/ -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html