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2020-08-04Cleanup: move zlib/lz4 code from lib/sqfs/comp/ to lib/David Oberhollenzer
The source code of a modified liblz4 and zlib are included with the option to compile them into libsquashfs if they are not available on the system. So far, the source code was included directly in the compressor sub directory within libsqsuashfs. This commit moves the libraries out into the lib directory. Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2020-05-19Cleanup: move hash table header to include directoryDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2020-04-27Add propper license text for Mesa hash table implementationDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2020-04-22Import and use Mesa's hash tableMatt Turner
With `perf record`/`perf report` I saw that 30% of the time was spent in `sqfs_frag_table_find_tail_end` with tar2sqfs for a tarball containing the Gentoo ebuild repository (many thousands of small files). The reason was the bucketing hash table in frag_table.c: too many elements in too few buckets meant lots of walking over the linked lists. This patch replaces that hash table with the hash table implementation from Mesa. Its implementation is more complex (is is an open-addressing, linear-reprobing) hash table, but it is much better suited for the task. On my 4c/8t Skylake, the time to run tar2sqfs drops from 7.5s to less than 3s. CPU usage increases from ~207% to ~356%, presumably indicating an increase in available parallelism due to the removal of the hash table as a bottleneck. The `perf report` profile with this patch shows that the time spent in `sqfs_frag_table_find_tail_end` has dropped from ~30% to 0.01%. Output from ministat: x before + after N Min Max Median Avg Stddev x 20 7.476 7.685 7.5725 7.5615 0.051254268 + 20 2.79 2.901 2.846 2.84475 0.03543842 Difference at 95.0% confidence -4.71675 +/- 0.0282015 -62.3785% +/- 0.241477% (Student's t, pooled s = 0.0440618) I imported only the bits of the hash table implementation that were needed for frag_table.c. Among the changes I made after importing are - removed usage of ralloc, Mesa's recursive memory allocator - Replaced ralloc -> malloc ralloc_free -> free rzalloc_array -> calloc - Removed mem_ctx parameters - Added free()s to the appropriate places (valgrind confirms there are no leaks) - removed _mesa_-prefix from function names Fixes: #40 Signed-off-by: Matt Turner <mattst88@gmail.com>
2020-04-22COPYING: Fix a couple of typosMatt Turner
Signed-off-by: Matt Turner <mattst88@gmail.com>
2020-03-18Cleanup: Move xxhash32 code to libutilDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2020-02-21Update README & COPYINGDavid Oberhollenzer
- Add libutil to the README file - Try to make the COPYING file somewhat more comprehensible Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2020-02-16Update the licensing documentation.David Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-11-25Cleanup: remove what is left of libutilDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
2019-11-24Update README, clarify licensing situationDavid Oberhollenzer
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>