While fixing the detection of symbolic links on OpenBSD I noticed
inconsistent behaviour:
$ echo hello > hello
$ ln -s hello world
$ zstd hello world
Warning : world is a symbolic link, ignoring
hello :316.67% ( 6 => 19 bytes, hello.zst
$ ls *.zst
hello.zst
$ zstd world
world :316.67% ( 6 => 19 bytes, world.zst)
$ ls *.zst
hello.zst world.zst
The `--no-progress` flag disables zstd's progress bars, but leaves
the summary.
I've added simple tests to `playTests.sh` to make sure the parsing
works.
For OSX and Linux, add a signal handler to SIGABRT, SGIFPE, SIGILL,
SIGSEGV, and SIGBUS. When the program terminates unexpectedly the
handler will print the current stack to the terminal to help determine
the location of the failure.
On OSX the output will look like:
```
Stack trace:
4 zstd 0x000000010927ed96 main + 16886
5 libdyld.dylib 0x00007fff767d1015 start + 1
6 ??? 0x0000000000000001 0x0 + 1
```
On Linux the output will look like:
```
Stack trace:
./zstd() [0x4b8e1b]
./zstd() [0x4b928a]
./zstd() [0x403dc2]
/lib64/libc.so.6(__libc_start_main+0xf5) [0x7f5e0fbb0445]
./zstd() [0x405754]
```
As is, the code does not function on WIN32.
See also: https://oroboro.com/stack-trace-on-crash/
* Minor fix
* Run non-optimize FASTCOVER 5 times in benchmark
* Merge fastCover into dictBuilder
* Fix mixed declaration issue
* Add fastcover to symbol.c
* Add fastCover.c and cover.h to build
* Change fastCover.c to fastcover.c
* Update benchmark to run FASTCOVER in dictBuilder
* Undo spliting fastcover_param into cover_param and f
* Remove convert param functions
* Assign f to parameter
* Add zdict.h to Makefile in lib
* Add cover.h to BUCK
* Cast 1 to U64 before shifting
* Remove trimming of zero freq head and tail in selectSegment and rebenchmark
* Remove f as a separate parameter of tryParam
* Read 8 bytes when d is 6
* Add trimming off zero frequency head and tail
* Use best functions from COVER and remove trimming part(which leads to worse compression ratio after previous bugs were fixed)
* Add finalize= argument to FASTCOVER to specify percentage of training samples passed to ZDICT_finalizeDictionary
* Change nbDmer to always read 8 bytes even when d=6
* Add skip=# argument to allow skipping dmers in computeFrequency in FASTCOVER
* Update comments and benchmarking result
* Change default method of ZDICT_trainFromBuffer to ZDICT_optimizeTrainFromBuffer_fastCover
* Add dictType enum and fix bug about passing zParam when converting to coverParam
* Combine finalize and skip into a single parameter
* Update acceleration parameters and benchmark on 3 sample sets
* Change default splitPoint of FASTCOVER to 0.75 and benchmark first 3 sample sets
* Initialize variables outside of for loop in benchmark.c
* Update benchmark result for hg-manifest
* Remove cover.h from install-includes
* Add explanation of f
* Set default compression level for trainFromBuffer to 3
* Add assertion of fastCoverParams in DiB_trainFromFiles
* Add checkTotalCompressedSize function + some minor fixes
* Add test for multithreading fastCovr
* Initialize segmentFreqs in every FASTCOVER_selectSegment and move mutex_unnlock to end of COVER_best_finish
* Free segmentFreqs
* Initialize segmentFreqs before calling FASTCOVER_buildDictionary instead of in FASTCOVER_selectSegment
* Add FASTCOVER_MEMMULT
* Minor fix
* Update benchmarking result
Seperate syntheticTest and fileTableTest (now renamed as benchFiles)
Add incremental display to benchMem
Change to only iterMode for benchFunction
Make Synthetic test's compressibility configurable from cli (using -P#)
-Remove global variables
-Remove gv setting functions
-Add advancedParams struct
-Add defaultAdvancedParams();
-Change return type of bench Files
-Change cli to use new interface
-Changed error returns to own struct value
-Change default compression benchmark to use decompress_generic
-Add CustomBench function
-Add Documentation for new functions
this makes it possible to specify extremely large negative compression levels,
achieving the side effect as "no compression".
It will also be possible to define larger targetlength for ultra compression mode.
There is no adverse side effect due to removing this limit.
access negative compression levels from command line
for both compression and benchmark modes.
also : ensure proper propagation of parameters
through ZSTD_compress_generic() interface.
added relevant cli tests.
zstd bench module can focus on decompression speed _only_.
This is useful when trying to measure performance
on large input data compressed using a high level
as compression time becomes problematic (too long).
This mode is triggered by command : zstd -b -d
Problem was : in such a mode,
measured decoding speed was > 10% slower
than in nominal mode (compression + decompression),
making decompression benchmark mode much less useful.
This patch fixes the issue.
It's not completely clear why, but
moving the `memcpy()` operation sooner in the pipeline fixed it.
I can still measure some difference, but it is in the < 2% range,
so it's much more tolerable.
also : it doesn't matter anymore in which order are selected
commands `-b` and `-d`.
The combination always triggers bench_decodeOnly mode.
This makes it easier to explain that nbWorkers=0 --> single-threaded mode,
while nbWorkers=1 --> asynchronous mode (one mode thread on top of the "main" caller thread).
No need for an additional asynchronous mode flag.
nbWorkers>=2 works the same as nbThreads>=2 previously.
added some test
also updated relevant doc
+ fixed a mistake in `lz4` symlink support :
lz4 utility doesn't remove source files by default (like zstd, but unlike gzip).
The symlink must behave the same.
Currently, all files are joined by default,
they are compressed separately but benchmarked together,
providing a single final result.
Benchmarking files separately make it possible to accurately measure difference for each file.
This is expected to be useful while tuning optimal parser.
* Maximum window size in 32-bit mode is 1GB, since allocations for 2GB fail
on my Mac.
* Maximum window size in 64-bit mode is 2GB, since that is the largest
power of 2 that works with the overflow prevention.
* Allow `--long=windowLog` to set the window log, along with
`--zstd=wlog=#`. These options also set the window size during
decompression, but don't override `--memory=#` if it is set.
* Present a helpful error message when the window size is too large during
decompression.
* The long range matcher defaults to a hash log 7 less than the window log,
which keeps it at 20 for window log 27.
* Keep the default long range matcher window size and the default maximum
window size at 27 for the API and CLI.
* Add tests that use the maximum window size and hash size for compression
and decompression.
file-information is dependent on decompression functions.
it should only be enabled when ZSTD_NODECOMPRESS is not set.
also : added zstd-compress compilation test into `make shortest`
now works with the `=` variant, which is the recommended one.
Old variant `--dictID #` still works, for compatibility with existing scripts.
Long term objective is to remove the old variant..
when zstd is called through a link named gzip, gunzip or gzcat,
provides the same behavior as the related program.
gzip compresses using --format=gz
both gzip and gunzip enable --rm by default
By default, section sizes are 4x window size.
This new setting allow manual selection of section sizes.
The larger they are, the (slightly) better the compression ratio,
but also the higher the memory allocation cost,
and eventually the lesser the nb of possible threads,
since each section is compressed by a single thread.
It also introduces a prototype to set generic parameters,
ZSTDMT_setMTCtxParameter()
The idea is that it's possible to add enums
to extend the list of parameters that can be set this way.
This is more long-term oriented than a fixed-size struct.
Consider it as a test.
