kernel.git/Documentation/admin-guide/ext4.rst, branch linux-5.8.y

ext4: limit the length of per-inode prealloc list

2020-09-03T09:29:37Z

[ Upstream commit 27bc446e2def38db3244a6eb4bb1d6312936610a ] In the scenario of writing sparse files, the per-inode prealloc list may be very long, resulting in high overhead for ext4_mb_use_preallocated(). To circumvent this problem, we limit the maximum length of per-inode prealloc list to 512 and allow users to modify it. After patching, we observed that the sys ratio of cpu has dropped, and the system throughput has increased significantly. We created a process to write the sparse file, and the running time of the process on the fixed kernel was significantly reduced, as follows: Running time on unfixed kernel： [root@TENCENT64 ~]# time taskset 0x01 ./sparse /data1/sparce.dat real 0m2.051s user 0m0.008s sys 0m2.026s Running time on fixed kernel： [root@TENCENT64 ~]# time taskset 0x01 ./sparse /data1/sparce.dat real 0m0.471s user 0m0.004s sys 0m0.395s Signed-off-by: Chunguang Xu Link: https://lore.kernel.org/r/d7a98178-056b-6db5-6bce-4ead23f4a257@gmail.com Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin

docs: ext4.rst: add encryption and verity to features list

2020-01-17T21:24:53Z

Mention encryption and verity in the ext4 features list. Signed-off-by: Eric Biggers Link: https://lore.kernel.org/r/20191226154007.4569-1-ebiggers@kernel.org Signed-off-by: Theodore Ts'o

ext4: clarify impact of 'commit' mount option

2019-12-22T02:36:53Z

The description of 'commit' mount option dates back to ext3 times. Update the description to match current meaning for ext4. Reported-by: Paul Richards Signed-off-by: Jan Kara Link: https://lore.kernel.org/r/20191218111210.14161-1-jack@suse.cz Signed-off-by: Theodore Ts'o

docs: ext4.rst: document case-insensitive directories

2019-04-25T18:13:27Z

Introduces the case-insensitive features on ext4 for system administrators. Explain the minimum of design decisions that are important for sysadmins wanting to enable this feature. Signed-off-by: Gabriel Krisman Bertazi Signed-off-by: Theodore Ts'o

docs: move ext4 administrative docs to admin-guide/

2018-10-05T23:11:59Z

Move the ext4 mount option and other administrative stuff to the Linux administrator's guide. Signed-off-by: Darrick J. Wong Signed-off-by: Theodore Ts'o