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LU-12477 ldiskfs: remove obsolete ext4 patches
[fs/lustre-release.git] / ldiskfs / kernel_patches / patches / rhel7.6 / ext4-preread-gd.patch
diff --git a/ldiskfs/kernel_patches/patches/rhel7.6/ext4-preread-gd.patch b/ldiskfs/kernel_patches/patches/rhel7.6/ext4-preread-gd.patch
new file mode 100644 (file)
index 0000000..db3abe6
--- /dev/null
@@ -0,0 +1,29 @@
+commit 85c8f176a6111ecde9c158109989dbd445a0e59a
+Author: Andrew Perepechko <andrew.perepechko@seagate.com>
+AuthorDate: Sun Apr 30 00:46:35 2017 -0400
+Commit: Theodore Ts'o <tytso@mit.edu>
+CommitDate: Sun Apr 30 00:46:35 2017 -0400
+ext4: preload block group descriptors
+
+With enabled meta_bg option block group descriptors
+reading IO is not sequential and requires optimization.
+
+Signed-off-by: Andrew Perepechko <andrew.perepechko@seagate.com>
+Signed-off-by: Theodore Ts'o <tytso@mit.edu>
+Index: fs/ext4/super.c
+===================================================================
+--- linux-stage/fs/ext4/super.c.orig
++++ linux-stage.orig/fs/ext4/super.c
+@@ -3918,6 +3919,12 @@ static int ext4_fill_super(struct super_
+       bgl_lock_init(sbi->s_blockgroup_lock);
++      /* Pre-read the descriptors into the buffer cache */
++      for (i = 0; i < db_count; i++) {
++              block = descriptor_loc(sb, logical_sb_block, i);
++              sb_breadahead(sb, block);
++      }
++
+       for (i = 0; i < db_count; i++) {
+               block = descriptor_loc(sb, logical_sb_block, i);
+               sbi->s_group_desc[i] = sb_bread(sb, block);