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@@ -64,6 +64,66 @@ obtained from this site also.
The squashfs-tools development tree is now located on kernel.org
git://git.kernel.org/pub/scm/fs/squashfs/squashfs-tools.git
+2.1 Mount options
+-----------------
+=================== =========================================================
+errors=%s Specify whether squashfs errors trigger a kernel panic
+ or not
+
+ ========== =============================================
+ continue errors don't trigger a panic (default)
+ panic trigger a panic when errors are encountered,
+ similar to several other filesystems (e.g.
+ btrfs, ext4, f2fs, GFS2, jfs, ntfs, ubifs)
+
+ This allows a kernel dump to be saved,
+ useful for analyzing and debugging the
+ corruption.
+ ========== =============================================
+threads=%s Select the decompression mode or the number of threads
+
+ If SQUASHFS_CHOICE_DECOMP_BY_MOUNT is set:
+
+ ========== =============================================
+ single use single-threaded decompression (default)
+
+ Only one block (data or metadata) can be
+ decompressed at any one time. This limits
+ CPU and memory usage to a minimum, but it
+ also gives poor performance on parallel I/O
+ workloads when using multiple CPU machines
+ due to waiting on decompressor availability.
+ multi use up to two parallel decompressors per core
+
+ If you have a parallel I/O workload and your
+ system has enough memory, using this option
+ may improve overall I/O performance. It
+ dynamically allocates decompressors on a
+ demand basis.
+ percpu use a maximum of one decompressor per core
+
+ It uses percpu variables to ensure
+ decompression is load-balanced across the
+ cores.
+ 1|2|3|... configure the number of threads used for
+ decompression
+
+ The upper limit is num_online_cpus() * 2.
+ ========== =============================================
+
+ If SQUASHFS_CHOICE_DECOMP_BY_MOUNT is **not** set and
+ SQUASHFS_DECOMP_MULTI, SQUASHFS_MOUNT_DECOMP_THREADS are
+ both set:
+
+ ========== =============================================
+ 2|3|... configure the number of threads used for
+ decompression
+
+ The upper limit is num_online_cpus() * 2.
+ ========== =============================================
+
+=================== =========================================================
+
3. Squashfs Filesystem Design
-----------------------------