@@ -772,23 +772,3 @@ core.magic = 0x494e
The chunk record also indicates that this chunk has 32 inodes, and that the
missing inodes are also ``free''.
-
-[[Real-time_Devices]]
-== Real-time Devices
-
-The performance of the standard XFS allocator varies depending on the internal
-state of the various metadata indices enabled on the filesystem. For
-applications which need to minimize the jitter of allocation latency, XFS
-supports the notion of a ``real-time device''. This is a special device
-separate from the regular filesystem where extent allocations are tracked with
-a bitmap and free space is indexed with a two-dimensional array. If an inode
-is flagged with +XFS_DIFLAG_REALTIME+, its data will live on the real time
-device. The metadata for real time devices is discussed in the section about
-xref:Real-time_Inodes[real time inodes].
-
-By placing the real time device (and the journal) on separate high-performance
-storage devices, it is possible to reduce most of the unpredictability in I/O
-response times that come from metadata operations.
-
-None of the XFS per-AG B+trees are involved with real time files. It is not
-possible for real time files to share data blocks.
@@ -287,41 +287,9 @@ Log sequence number of the last DQ block write.
*dd_crc*::
Checksum of the DQ block.
-
[[Real-time_Inodes]]
== Real-time Inodes
There are two inodes allocated to managing the real-time device's space, the
-Bitmap Inode and the Summary Inode.
-
-[[Real-Time_Bitmap_Inode]]
-=== Real-Time Bitmap Inode
-
-The real time bitmap inode, +sb_rbmino+, tracks the used/free space in the
-real-time device using an old-style bitmap. One bit is allocated per real-time
-extent. The size of an extent is specified by the superblock's +sb_rextsize+
-value.
-
-The number of blocks used by the bitmap inode is equal to the number of
-real-time extents (+sb_rextents+) divided by the block size (+sb_blocksize+)
-and bits per byte. This value is stored in +sb_rbmblocks+. The nblocks and
-extent array for the inode should match this. Each real time block gets its
-own bit in the bitmap.
-
-[[Real-Time_Summary_Inode]]
-=== Real-Time Summary Inode
-
-The real time summary inode, +sb_rsumino+, tracks the used and free space
-accounting information for the real-time device. This file indexes the
-approximate location of each free extent on the real-time device first by
-log2(extent size) and then by the real-time bitmap block number. The size of
-the summary inode file is equal to +sb_rbmblocks+ × log2(realtime device size)
-× sizeof(+xfs_suminfo_t+). The entry for a given log2(extent size) and
-rtbitmap block number is 0 if there is no free extents of that size at that
-rtbitmap location, and positive if there are any.
-
-This data structure is not particularly space efficient, however it is a very
-fast way to provide the same data as the two free space B+trees for regular
-files since the space is preallocated and metadata maintenance is minimal.
-
-include::rtrmapbt.asciidoc[]
+xref:Real-Time_Bitmap_Inode[Bitmap Inode] and the
+xref:Real-Time_Summary_Inode[Summary Inode].
new file mode 100644
@@ -0,0 +1,50 @@
+[[Real-time_Devices]]
+= Real-time Devices
+
+The performance of the standard XFS allocator varies depending on the internal
+state of the various metadata indices enabled on the filesystem. For
+applications which need to minimize the jitter of allocation latency, XFS
+supports the notion of a ``real-time device''. This is a special device
+separate from the regular filesystem where extent allocations are tracked with
+a bitmap and free space is indexed with a two-dimensional array. If an inode
+is flagged with +XFS_DIFLAG_REALTIME+, its data will live on the real time
+device.
+
+By placing the real time device (and the journal) on separate high-performance
+storage devices, it is possible to reduce most of the unpredictability in I/O
+response times that come from metadata operations.
+
+None of the XFS per-AG B+trees are involved with real time files. It is not
+possible for real time files to share data blocks.
+
+[[Real-Time_Bitmap_Inode]]
+== Free Space Bitmap Inode
+
+The real time bitmap inode, +sb_rbmino+, tracks the used/free space in the
+real-time device using an old-style bitmap. One bit is allocated per real-time
+extent. The size of an extent is specified by the superblock's +sb_rextsize+
+value.
+
+The number of blocks used by the bitmap inode is equal to the number of
+real-time extents (+sb_rextents+) divided by the block size (+sb_blocksize+)
+and bits per byte. This value is stored in +sb_rbmblocks+. The nblocks and
+extent array for the inode should match this. Each real time block gets its
+own bit in the bitmap.
+
+[[Real-Time_Summary_Inode]]
+== Free Space Summary Inode
+
+The real time summary inode, +sb_rsumino+, tracks the used and free space
+accounting information for the real-time device. This file indexes the
+approximate location of each free extent on the real-time device first by
+log2(extent size) and then by the real-time bitmap block number. The size of
+the summary inode file is equal to +sb_rbmblocks+ × log2(realtime device size)
+× sizeof(+xfs_suminfo_t+). The entry for a given log2(extent size) and
+rtbitmap block number is 0 if there is no free extents of that size at that
+rtbitmap location, and positive if there are any.
+
+This data structure is not particularly space efficient, however it is a very
+fast way to provide the same data as the two free space B+trees for regular
+files since the space is preallocated and metadata maintenance is minimal.
+
+include::rtrmapbt.asciidoc[]
@@ -84,6 +84,8 @@ include::journaling_log.asciidoc[]
include::internal_inodes.asciidoc[]
+include::realtime.asciidoc[]
+
include::fs_properties.asciidoc[]
:leveloffset: 0