From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f41.google.com (mail-pa0-f41.google.com [209.85.220.41]) by kanga.kvack.org (Postfix) with ESMTP id DE8ED6B0036 for ; Mon, 4 Nov 2013 05:43:09 -0500 (EST) Received: by mail-pa0-f41.google.com with SMTP id rd3so6896228pab.0 for ; Mon, 04 Nov 2013 02:43:09 -0800 (PST) Received: from psmtp.com ([74.125.245.170]) by mx.google.com with SMTP id gv2si10141874pbb.281.2013.11.04.02.43.03 for ; Mon, 04 Nov 2013 02:43:04 -0800 (PST) From: "Kirill A. Shutemov" In-Reply-To: <1382442839-7458-1-git-send-email-kirill.shutemov@linux.intel.com> References: <1382442839-7458-1-git-send-email-kirill.shutemov@linux.intel.com> Subject: RE: [PATCH] mm: create a separate slab for page->ptl allocation Content-Transfer-Encoding: 7bit Message-Id: <20131104104259.86AFEE0090@blue.fi.intel.com> Date: Mon, 4 Nov 2013 12:42:59 +0200 (EET) Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Peter Zijlstra , Ingo Molnar , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, "Kirill A. Shutemov" Kirill A. Shutemov wrote: > If DEBUG_SPINLOCK and DEBUG_LOCK_ALLOC are enabled spinlock_t on x86_64 > is 72 bytes. For page->ptl they will be allocated from kmalloc-96 slab, > so we loose 24 on each. An average system can easily allocate few tens > thousands of page->ptl and overhead is significant. > > Let's create a separate slab for page->ptl allocation to solve this. > > Signed-off-by: Kirill A. Shutemov ping? -- Kirill A. Shutemov -- 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