| Message ID | E8BB5200-9BE3-49FE-AFC2-18B2E7BBA5A8@whamcloud.com |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Dec 06, 2011 at 05:13:51PM -0700, Andreas Dilger wrote: > Reserve the EXT4_FEATURE_INCOMPAT_INLINEDATA feature flag for use > with storing small file data in the i_blocks field (up to 60 bytes) > and/or the large xattr space (after i_extra_isize, up to the large > inode size). On typical filesystems this can save 1-3% of the space, > and more importantly it also avoids seeking to read the data block. > > This will become increasingly important with bigalloc filesystems, > since they consume a full cluster of blocks for each file, including > small directories that could easily fit into the inode itself. > > Signed-off-by: Andreas Dilger <adilger@whamcloud.com> > Originally-by: Tao Ma <tm@tao.ma> > --- > lib/ext2fs/ext2_fs.h | 1 + > 1 files changed, 1 insertions(+), 0 deletions(-) > > diff --git a/lib/ext2fs/ext2_fs.h b/lib/ext2fs/ext2_fs.h > index 0f8cde8..6cf47f9 100644 > --- a/lib/ext2fs/ext2_fs.h > +++ b/lib/ext2fs/ext2_fs.h > @@ -719,6 +719,7 @@ struct ext2_super_block { > #define EXT4_FEATURE_INCOMPAT_FLEX_BG 0x0200 > #define EXT4_FEATURE_INCOMPAT_EA_INODE 0x0400 > #define EXT4_FEATURE_INCOMPAT_DIRDATA 0x1000 > +#define EXT4_FEATURE_INCOMPAT_INLINEDATA 0x2000 /* data in inode */ I was using 0x2000 for EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM, to change the block group checksum to use crc32c. --D > > #define EXT2_FEATURE_COMPAT_SUPP 0 > #define EXT2_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE| \ > -- > 1.7.2 > > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 12/07/2011 08:13 AM, Andreas Dilger wrote: > Reserve the EXT4_FEATURE_INCOMPAT_INLINEDATA feature flag for use > with storing small file data in the i_blocks field (up to 60 bytes) > and/or the large xattr space (after i_extra_isize, up to the large > inode size). On typical filesystems this can save 1-3% of the space, > and more importantly it also avoids seeking to read the data block. > > This will become increasingly important with bigalloc filesystems, > since they consume a full cluster of blocks for each file, including > small directories that could easily fit into the inode itself. > > Signed-off-by: Andreas Dilger <adilger@whamcloud.com> > Originally-by: Tao Ma <tm@tao.ma> I am fine with it. Thanks. Tao > --- > lib/ext2fs/ext2_fs.h | 1 + > 1 files changed, 1 insertions(+), 0 deletions(-) > > diff --git a/lib/ext2fs/ext2_fs.h b/lib/ext2fs/ext2_fs.h > index 0f8cde8..6cf47f9 100644 > --- a/lib/ext2fs/ext2_fs.h > +++ b/lib/ext2fs/ext2_fs.h > @@ -719,6 +719,7 @@ struct ext2_super_block { > #define EXT4_FEATURE_INCOMPAT_FLEX_BG 0x0200 > #define EXT4_FEATURE_INCOMPAT_EA_INODE 0x0400 > #define EXT4_FEATURE_INCOMPAT_DIRDATA 0x1000 > +#define EXT4_FEATURE_INCOMPAT_INLINEDATA 0x2000 /* data in inode */ > > #define EXT2_FEATURE_COMPAT_SUPP 0 > #define EXT2_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE| \ -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 2011-12-06, at 5:39 PM, Darrick J. Wong wrote: > On Tue, Dec 06, 2011 at 05:13:51PM -0700, Andreas Dilger wrote: >> +#define EXT4_FEATURE_INCOMPAT_INLINEDATA 0x2000 /* data in inode */ > > I was using 0x2000 for EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM, to change > the block group checksum to use crc32c. I didn't see that... I was looking at your patch and only noticed EXT4_FEATURE_RO_COMPAT_METADATA_CSUM. I suspect your patch is closer to landing it is better to use the 0x2000 value for BG_USE_META_CSUM, and change the value for INLINEDATA to 0x8000 instead. Cheers, Andreas -- Andreas Dilger Principal Engineer Whamcloud, Inc. -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 12/07/2011 05:45 PM, Andreas Dilger wrote: > On 2011-12-06, at 5:39 PM, Darrick J. Wong wrote: >> On Tue, Dec 06, 2011 at 05:13:51PM -0700, Andreas Dilger wrote: >>> +#define EXT4_FEATURE_INCOMPAT_INLINEDATA 0x2000 /* data in inode */ >> >> I was using 0x2000 for EXT4_FEATURE_INCOMPAT_BG_USE_META_CSUM, to change >> the block group checksum to use crc32c. > > I didn't see that... I was looking at your patch and only noticed > EXT4_FEATURE_RO_COMPAT_METADATA_CSUM. I suspect your patch is closer > to landing it is better to use the 0x2000 value for BG_USE_META_CSUM, > and change the value for INLINEDATA to 0x8000 instead. OK, I will use this number for inline data for the new version if there is no objection. Thanks Tao -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/lib/ext2fs/ext2_fs.h b/lib/ext2fs/ext2_fs.h index 0f8cde8..6cf47f9 100644 --- a/lib/ext2fs/ext2_fs.h +++ b/lib/ext2fs/ext2_fs.h @@ -719,6 +719,7 @@ struct ext2_super_block { #define EXT4_FEATURE_INCOMPAT_FLEX_BG 0x0200 #define EXT4_FEATURE_INCOMPAT_EA_INODE 0x0400 #define EXT4_FEATURE_INCOMPAT_DIRDATA 0x1000 +#define EXT4_FEATURE_INCOMPAT_INLINEDATA 0x2000 /* data in inode */ #define EXT2_FEATURE_COMPAT_SUPP 0 #define EXT2_FEATURE_INCOMPAT_SUPP (EXT2_FEATURE_INCOMPAT_FILETYPE| \
Reserve the EXT4_FEATURE_INCOMPAT_INLINEDATA feature flag for use with storing small file data in the i_blocks field (up to 60 bytes) and/or the large xattr space (after i_extra_isize, up to the large inode size). On typical filesystems this can save 1-3% of the space, and more importantly it also avoids seeking to read the data block. This will become increasingly important with bigalloc filesystems, since they consume a full cluster of blocks for each file, including small directories that could easily fit into the inode itself. Signed-off-by: Andreas Dilger <adilger@whamcloud.com> Originally-by: Tao Ma <tm@tao.ma> --- lib/ext2fs/ext2_fs.h | 1 + 1 files changed, 1 insertions(+), 0 deletions(-)