From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A9F85C46475 for ; Mon, 5 Nov 2018 15:02:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6ECB42085A for ; Mon, 5 Nov 2018 15:02:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="JNbdWJuT" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6ECB42085A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730049AbeKFAWG (ORCPT ); Mon, 5 Nov 2018 19:22:06 -0500 Received: from mail-ua1-f41.google.com ([209.85.222.41]:42749 "EHLO mail-ua1-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729473AbeKFAWG (ORCPT ); Mon, 5 Nov 2018 19:22:06 -0500 Received: by mail-ua1-f41.google.com with SMTP id d21so3266937uap.9 for ; Mon, 05 Nov 2018 07:01:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:from:date:message-id:subject:to; bh=OYIY3viVCF8vRikh06BNnK36L3xDHvAxFlHa4paMGwk=; b=JNbdWJuT110lq/LPIDECulFdJQWobV+AI5mn1yEoDlu7J9jbLjvcC09VytQjaTD1D2 maq+hprkr3jhcoq7kz83MifOGWe0NIKIXV9C63mB7Ho7Lw4sGCJnSvUjQzQ6UGahxyH3 uqEATZobInuvTFI7/Gh2GHtbI89xLK2CfST2uqGpkQ6lEVbxT8fs0sC0bk/7NawcIaTu 2LkGsH3mCRciQyuqwmPAoIX5qmOt/BSb7HNOKnzbDxH8sr0XfgXaf69Mbud2CbB24+2H YoAb387uGu2opBnXnvkFWpJPKGwNoiaSLT5b+vrTANbRKOYFZdoIYFRnLGsG+pBvD3+D Ih6A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to; bh=OYIY3viVCF8vRikh06BNnK36L3xDHvAxFlHa4paMGwk=; b=m5zOxVqKK/PSFbJE4ZXj3JOiKLOlnA4jwALfucFLXUvvrrxzSAyxNT2CIDP54Ur0kl 0/lLWUAZaw5IyASwEBKf9XhhlP4TFrr+oKr5dgw053C3kV5r/HUEJ0tWiZoEAn37xMSn VVNciVvuf+zcP7eZb6Fmd8JuV1tbgchIdXnIfu3PKVc46IpJgLykRwZ4g2TN1z4rgNoO X2s43XTIDs5MlxFZsveMNk1lsPToeu1GCmb2ZaEZbe27ltAYpgOF8JhiELo2RO1C5Ivx D2GS6hpHqOcRor2egfp+EkhszPBLoFisIMKWEti4c2nIedbij1WVFTF/JSioX5NNjOTN a7Kg== X-Gm-Message-State: AGRZ1gIgQHgogDyeRBRJMam6gdoxqFX8n0o+nrwSRULfaeR5Fify9kBh Eyg9ILSXjBZBnmrf7Wz1/sCiPpFZ8uTNI4zZZGmIsA== X-Google-Smtp-Source: AJdET5c020ARybs4AmbD9JlU8XGm7imVDmj70HPH9AQUwvxFz2fNa9mjJtspSyAskE3ne1MSGE0x0+JoXppWXiDfxuo= X-Received: by 2002:ab0:1553:: with SMTP id p19mr6625692uae.47.1541430118298; Mon, 05 Nov 2018 07:01:58 -0800 (PST) MIME-Version: 1.0 From: Pintu Agarwal Date: Mon, 5 Nov 2018 20:31:46 +0530 Message-ID: Subject: Creating compressed backing_store as swapfile To: linux-mm@kvack.org, open list , kernelnewbies@kernelnewbies.org Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, I have one requirement: I wanted to have a swapfile (64MB to 256MB) on my system. But I wanted the data to be compressed and stored on the disk in my swapfile. [Similar to zram, but compressed data should be moved to disk, instead of RAM]. Note: I wanted to optimize RAM space, so performance is not important right now for our requirement. So, what are the options available, to perform this in 4.x kernel version. My Kernel: 4.9.x Board: any - (arm64 mostly). As I know, following are the choices: 1) ZRAM: But it compresses and store data in RAM itself 2) frontswap + zswap : Didn't explore much on this, not sure if this is helpful for our case. 3) Manually creating swapfile: but how to compress it ? 4) Any other options ? Thanks, Pintu