ext4.5, tune2fs.8: add documentation for the orphan_file feature

Add documentation for the orphan_file feature to the ext4(5) and
tune2fs(8) man pages.

Addresses-Debian-Bug: #1073062
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/misc/ext4.5.in b/misc/ext4.5.in
index cf73bdf04239ffea801175bad2dacdeda63b7d45..e909fd179d3c510009a0ba49b25ff1dd4f805dc2 100644 (file)
--- a/misc/ext4.5.in
+++ b/misc/ext4.5.in
@@ -245,6 +245,13 @@ This ext4 feature provides multiple mount protection (MMP).  MMP helps to
 protect the file system from being multiply mounted and is useful in
 shared storage environments.
 .TP
+.B orphan_file
+.br
+This ext4 feature fixes a potential scalability bottleneck for workloads
+that are doing a large number of truncate or file extensions in
+parallel.  It is supported by Linux kernels starting version 5.15, and
+by e2fsprogs starting with version 1.47.0.
+.TP
 .B project
 .br
 This ext4 feature provides project quota support. With this feature,

diff --git a/misc/tune2fs.8.in b/misc/tune2fs.8.in
index c233494eda45a299e7e3702e870c7be28d73a847..ff0bd511539623c1a8406b97abfa6304f97f0434 100644 (file)
--- a/misc/tune2fs.8.in
+++ b/misc/tune2fs.8.in
@@ -669,6 +669,11 @@ feature while it is mounted.
 .B mmp
 Enable or disable multiple mount protection (MMP) feature.
 .TP
+.B orphan_file
+Store the list of orphan inodes in multiple blocks instead of a single
+linked-list to avoid potential scalability bottlenecks for workloads
+that perform a large number of file truncations or extensions in parallel.
+.TP
 .B project
 Enable project ID tracking.  This is used for project quota tracking.
 .TP