Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754698AbbFTL2h (ORCPT ); Sat, 20 Jun 2015 07:28:37 -0400 Received: from mail-wi0-f179.google.com ([209.85.212.179]:37259 "EHLO mail-wi0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752940AbbFTL2a (ORCPT ); Sat, 20 Jun 2015 07:28:30 -0400 From: Ebru Akagunduz To: linux-mm@kvack.org Cc: akpm@linux-foundation.org, kirill.shutemov@linux.intel.com, n-horiguchi@ah.jp.nec.com, aarcange@redhat.com, riel@redhat.com, iamjoonsoo.kim@lge.com, xiexiuqi@huawei.com, gorcunov@openvz.org, linux-kernel@vger.kernel.org, mgorman@suse.de, rientjes@google.com, vbabka@suse.cz, aneesh.kumar@linux.vnet.ibm.com, hughd@google.com, hannes@cmpxchg.org, mhocko@suse.cz, boaz@plexistor.com, raindel@mellanox.com, Ebru Akagunduz Subject: [RFC v2 0/3] mm: make swapin readahead to gain more thp performance Date: Sat, 20 Jun 2015 14:28:03 +0300 Message-Id: <1434799686-7929-1-git-send-email-ebru.akagunduz@gmail.com> X-Mailer: git-send-email 1.9.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2438 Lines: 58 This patch series makes swapin readahead up to a certain number to gain more thp performance and adds tracepoint for khugepaged_scan_pmd, collapse_huge_page, __collapse_huge_page_isolate. This patch series was written to deal with programs that access most, but not all, of their memory after they get swapped out. Currently these programs do not get their memory collapsed into THPs after the system swapped their memory out, while they would get THPs before swapping happened. This patch series was tested with a test program, it allocates 800MB of memory, writes to it, and then sleeps. I force the system to swap out all. Afterwards, the test program touches the area by writing and leaves a piece of it without writing. This shows how much swap in readahead made by the patch. Test results: After swapped out ------------------------------------------------------------------- | Anonymous | AnonHugePages | Swap | Fraction | ------------------------------------------------------------------- With patch | 265772 kB | 264192 kB | 534232 kB | %99 | ------------------------------------------------------------------- Without patch | 238160 kB | 235520 kB | 561844 kB | %98 | ------------------------------------------------------------------- After swapped in ------------------------------------------------------------------- | Anonymous | AnonHugePages | Swap | Fraction | ------------------------------------------------------------------- With patch | 532756 kB | 528384 kB | 267248 kB | %99 | ------------------------------------------------------------------- Without patch | 499956 kB | 235520 kB | 300048 kB | %47 | ------------------------------------------------------------------- Ebru Akagunduz (3): mm: add tracepoint for scanning pages mm: make optimistic check for swapin readahead mm: make swapin readahead to improve thp collapse rate include/linux/mm.h | 4 ++ include/trace/events/huge_memory.h | 123 +++++++++++++++++++++++++++++++++++++ mm/huge_memory.c | 58 ++++++++++++++++- mm/memory.c | 2 +- 4 files changed, 183 insertions(+), 4 deletions(-) create mode 100644 include/trace/events/huge_memory.h -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in Please read the FAQ at http://www.tux.org/lkml/