diff --git a/doc/usage/cmd/blkcache.rst b/doc/usage/cmd/blkcache.rst new file mode 100644 index 0000000000..d3b2254cfa --- /dev/null +++ b/doc/usage/cmd/blkcache.rst @@ -0,0 +1,74 @@ +.. SPDX-License-Identifier: GPL-2.0+ +.. Copyright 2023, Heinrich Schuchardt + +blkcache command +================ + +Synopsis +-------- + +:: + + blkcache show + blkcache configure + +Description +----------- + +The *blkcache* command is used to control the size of the block cache and to +display statistics. + +The block cache buffers data read from block devices. This speeds up the access +to file-systems. + +show + show and reset statistics + +configure + set the maximum number of cache entries and the maximum number of blocks per + entry + +blocks + maximum number of blocks per cache entry. The block size is device specific. + The initial value is 8. + +entries + maximum number of entries in the cche. The initial value is 32. + +Example +------- + +.. code-block:: + + => blkcache show + hits: 296 + misses: 149 + entries: 7 + max blocks/entry: 8 + max cache entries: 32 + => blkcache show + hits: 0 + misses: 0 + entries: 7 + max blocks/entry: 8 + max cache entries: 32 + => blkcache configure 16 64 + changed to max of 64 entries of 16 blocks each + => blkcache show + hits: 0 + misses: 0 + entries: 0 + max blocks/entry: 16 + max cache entries: 64 + => + +Configuration +------------- + +The blkcache command is only available if CONFIG_CMD_BLOCK_CACHE=y. + +Return code +----------- + +If the command succeeds, the return code $? is set 0 (true). In case of an +error the return code is set to 1 (false). diff --git a/doc/usage/index.rst b/doc/usage/index.rst index 53e4aeec56..9284d159d7 100644 --- a/doc/usage/index.rst +++ b/doc/usage/index.rst @@ -23,6 +23,7 @@ Shell commands cmd/addrmap cmd/askenv cmd/base + cmd/blkcache cmd/bootd cmd/bootdev cmd/bootefi