From 5e76619fcda3d792b2cb188fc2d950c61d7ebf09 Mon Sep 17 00:00:00 2001 From: David Sterba Date: Tue, 21 Jul 2020 12:28:05 +0200 Subject: [PATCH 2/2] btrfs-progs: mkfs: switch to single as default profile for multiple-devices The single profile is better suited as default for data on multiple devices. Switch from RAID0 because: - it's easier to convert to other profiles, as single consumes some chunks per device, but RAID0 has chunks on all devices regardless of the used space - RAID0 has no redundancy and compared one disk failure affects many files due to striping, while with single the chances are a bit higher that complete files are stored on one device - when the device sizes are not equal and not even close to equal, the maximum achievable size with RAID0 is size of the smallest device due to striping, with single it's the sum of all device sizes The changed defaults could affect scripts and deployments that rely on the old values, but given the number of possible profiles for multiple devices let's hope that they're specified explicitly in majority of cases. Issue: #270 Signed-off-by: David Sterba (cherry picked from commit f1507716c67e2d6012f1e7a0f1538d4f669faa23) --- mkfs/common.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mkfs/common.h b/mkfs/common.h index 61969dcc..cc88db71 100644 --- a/mkfs/common.h +++ b/mkfs/common.h @@ -35,7 +35,7 @@ #define BTRFS_MKFS_DEFAULT_META_ONE_DEVICE BTRFS_BLOCK_GROUP_DUP #define BTRFS_MKFS_DEFAULT_META_ONE_DEVICE_SSD 0 /* SINGLE */ -#define BTRFS_MKFS_DEFAULT_DATA_MULTI_DEVICE BTRFS_BLOCK_GROUP_RAID0 +#define BTRFS_MKFS_DEFAULT_DATA_MULTI_DEVICE 0 /* SINGLE */ #define BTRFS_MKFS_DEFAULT_META_MULTI_DEVICE BTRFS_BLOCK_GROUP_RAID1 /* -- 2.26.2