From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f50.google.com (mail-pa0-f50.google.com [209.85.220.50]) by kanga.kvack.org (Postfix) with ESMTP id 9D7C16B0071 for ; Mon, 16 Mar 2015 19:53:56 -0400 (EDT) Received: by pabyw6 with SMTP id yw6so79314605pab.2 for ; Mon, 16 Mar 2015 16:53:56 -0700 (PDT) Received: from userp1040.oracle.com (userp1040.oracle.com. [156.151.31.81]) by mx.google.com with ESMTPS id xh9si25456881pab.119.2015.03.16.16.53.54 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Mon, 16 Mar 2015 16:53:55 -0700 (PDT) From: Mike Kravetz Subject: [PATCH V2 4/4] hugetlbfs: document min_size mount option Date: Mon, 16 Mar 2015 16:53:29 -0700 Message-Id: <3c82f2203e5453ddf3b29431863034afc7699303.1426549011.git.mike.kravetz@oracle.com> In-Reply-To: References: In-Reply-To: References: Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: Andrew Morton , Davidlohr Bueso , Aneesh Kumar , Joonsoo Kim , Mike Kravetz Update documentation for the hugetlbfs min_size mount option. Signed-off-by: Mike Kravetz --- Documentation/vm/hugetlbpage.txt | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/Documentation/vm/hugetlbpage.txt b/Documentation/vm/hugetlbpage.txt index f2d3a10..83c0305 100644 --- a/Documentation/vm/hugetlbpage.txt +++ b/Documentation/vm/hugetlbpage.txt @@ -267,8 +267,8 @@ call, then it is required that system administrator mount a file system of type hugetlbfs: mount -t hugetlbfs \ - -o uid=,gid=,mode=,size=,nr_inodes= \ - none /mnt/huge + -o uid=,gid=,mode=,size=,min_size=, \ + nr_inodes= none /mnt/huge This command mounts a (pseudo) filesystem of type hugetlbfs on the directory /mnt/huge. Any files created on /mnt/huge uses huge pages. The uid and gid @@ -277,11 +277,18 @@ the uid and gid of the current process are taken. The mode option sets the mode of root of file system to value & 01777. This value is given in octal. By default the value 0755 is picked. The size option sets the maximum value of memory (huge pages) allowed for that filesystem (/mnt/huge). The size is -rounded down to HPAGE_SIZE. The option nr_inodes sets the maximum number of -inodes that /mnt/huge can use. If the size or nr_inodes option is not -provided on command line then no limits are set. For size and nr_inodes -options, you can use [G|g]/[M|m]/[K|k] to represent giga/mega/kilo. For -example, size=2K has the same meaning as size=2048. +rounded down to HPAGE_SIZE. The min_size option sets the minimum value of +memory (huge pages) allowed for the filesystem. Like the size option, +min_size is rounded down to HPAGE_SIZE. At mount time, the number of huge +pages specified by min_size are reserved for use by the filesystem. If +there are not enough free huge pages available, the mount will fail. As +huge pages are allocated to the filesystem and freed, the reserve count +is adjusted so that the sum of allocated and reserved huge pages is always +at least min_size. The option nr_inodes sets the maximum number of +inodes that /mnt/huge can use. If the size, min_size or nr_inodes option +is not provided on command line then no limits are set. For size, min_size +and nr_inodes options, you can use [G|g]/[M|m]/[K|k] to represent +giga/mega/kilo. For example, size=2K has the same meaning as size=2048. While read system calls are supported on files that reside on hugetlb file systems, write system calls are not. -- 2.1.0 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org