From 32eb57dd9a19254565a0792ab9b627a3dac319f9 Mon Sep 17 00:00:00 2001 From: David Oberhollenzer Date: Sat, 4 Mar 2023 21:28:14 +0100 Subject: libsquashfs: remove the default block writer alignment feature The idea of the block align feature was to allow micro-managing that some files are forcefully aligned to 1k/4k ("device block") boundaries, hoping to improve access time at the cost of data density. The feature was not exposed in the tools for a long time and eventuall added to the sort file. Measurement and experimentation showed, that it in fact worsened the read performance on a test system with an old micro SD card as the bottle neck. The feature is removed, and if needed, can be brought back simply by wrapping/sub-classing the default block writer, if need be.. Signed-off-by: David Oberhollenzer --- include/sqfs/block.h | 16 ++++------------ 1 file changed, 4 insertions(+), 12 deletions(-) (limited to 'include/sqfs/block.h') diff --git a/include/sqfs/block.h b/include/sqfs/block.h index 30f181c..639fb68 100644 --- a/include/sqfs/block.h +++ b/include/sqfs/block.h @@ -72,12 +72,9 @@ typedef enum { SQFS_BLK_DONT_COMPRESS = 0x0001, /** - * @brief Align the block on disk to device block size. - * - * If set, the @ref sqfs_block_processor_t will add padding before the - * first block of the affected file and after the last block. + * @brief Don't compute block data checksums. */ - SQFS_BLK_ALIGN = 0x0002, + SQFS_BLK_DONT_HASH = 0x0002, /** * @brief Don't add the tail end of a file to a fragment block. @@ -104,11 +101,6 @@ typedef enum { */ SQFS_BLK_IGNORE_SPARSE = 0x0010, - /** - * @brief Don't compute block data checksums. - */ - SQFS_BLK_DONT_HASH = 0x0020, - /** * @brief Set by the @ref sqfs_block_processor_t if it determines a * block of a file to be sparse, i.e. only zero bytes. @@ -148,9 +140,9 @@ typedef enum { /** * @brief The combination of all flags that are user settable. */ - SQFS_BLK_USER_SETTABLE_FLAGS = 0x003F, + SQFS_BLK_USER_SETTABLE_FLAGS = 0x001F, - SQFS_BLK_FLAGS_ALL = 0xFC3F, + SQFS_BLK_FLAGS_ALL = 0xFC1F, } SQFS_BLK_FLAGS; #endif /* SQFS_BLOCK_H */ -- cgit v1.2.3