Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752525Ab1FTQfx (ORCPT ); Mon, 20 Jun 2011 12:35:53 -0400 Received: from mx1.redhat.com ([209.132.183.28]:2705 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751945Ab1FTQfv (ORCPT ); Mon, 20 Jun 2011 12:35:51 -0400 From: Amerigo Wang To: linux-kernel@vger.kernel.org Cc: akpm@linux-foundation.org, Amerigo Wang , Andrea Arcangeli , Mel Gorman , Benjamin Herrenschmidt , Rik van Riel , Johannes Weiner , KAMEZAWA Hiroyuki , linux-mm@kvack.org Subject: [PATCH 2/3] mm: make the threshold of enabling THP configurable Date: Tue, 21 Jun 2011 00:34:29 +0800 Message-Id: <1308587683-2555-2-git-send-email-amwang@redhat.com> In-Reply-To: <1308587683-2555-1-git-send-email-amwang@redhat.com> References: <1308587683-2555-1-git-send-email-amwang@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1597 Lines: 51 Don't hard-code 512M as the threshold in kernel, make it configruable, and set 512M by default. Signed-off-by: WANG Cong --- mm/Kconfig | 10 ++++++++++ mm/huge_memory.c | 2 +- 2 files changed, 11 insertions(+), 1 deletions(-) diff --git a/mm/Kconfig b/mm/Kconfig index 8ca47a5..a826471 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -340,6 +340,16 @@ choice benefit. endchoice +config TRANSPARENT_HUGEPAGE_THRESHOLD + depends on TRANSPARENT_HUGEPAGE + int "The minimal threshold of enabling Transparent Hugepage" + range 512 8192 + default "512" + help + The threshold of enabling Transparent Huagepage automatically, + in Mbytes, below this value, Transparent Hugepage will be disabled + by default during boot. + # # UP and nommu archs use km based percpu allocator # diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 9c63c90..7fb44cc 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -544,7 +544,7 @@ static int __init hugepage_init(void) * where the extra memory used could hurt more than TLB overhead * is likely to save. The admin can still enable it through /sys. */ - if (totalram_pages < (512 << (20 - PAGE_SHIFT))) + if (totalram_pages < (CONFIG_TRANSPARENT_HUGEPAGE_THRESHOLD << (20 - PAGE_SHIFT))) transparent_hugepage_flags = 0; start_khugepaged(); -- 1.7.4.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/