Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754144AbbHRTMl (ORCPT ); Tue, 18 Aug 2015 15:12:41 -0400 Received: from mail-wi0-f170.google.com ([209.85.212.170]:35586 "EHLO mail-wi0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753570AbbHRTMk (ORCPT ); Tue, 18 Aug 2015 15:12:40 -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 v4 0/3] mm: make swapin readahead to gain more thp performance Date: Tue, 18 Aug 2015 22:11:04 +0300 Message-Id: <1439925067-5514-1-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: 2598 Lines: 60 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 | 253720 kB | 251904 kB | 546284 kB | %99 | ------------------------------------------------------------------- Without patch | 238160 kB | 235520 kB | 561844 kB | %98 | ------------------------------------------------------------------- After swapped in ------------------------------------------------------------------- | Anonymous | AnonHugePages | Swap | Fraction | ------------------------------------------------------------------- With patch | 533532 kB | 528384 kB | 266472 kB | %90 | ------------------------------------------------------------------- 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 | 126 +++++++++++++++++ mm/huge_memory.c | 274 ++++++++++++++++++++++++++++++++----- mm/memory.c | 2 +- 4 files changed, 373 insertions(+), 33 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 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/