<div>Hello,</div><div><br></div><div>Koen suggested to add -T to xz commands. We have this option implemented in our current version .1alpha. </div><div><br></div><div><div>-T threads, --threads=threads                                                                                                                                                                                                         </div>


<div>              Specify the number of worker threads to use.  Setting threads to                                                                                                                                                               </div>


<div>              a special value 0 makes xz use as many threads as there are  CPU                                                                                                                                                               </div>


<div>              cores  on  the system.  The actual number of threads can be less                                                                                                                                                               </div>


<div>              than threads if the input file is not big enough  for  threading                                                                                                                                                               </div>


<div>              with  the  given  settings or if using more threads would exceed                                                                                                                                                               </div>


<div>              the memory usage limit.</div></div><div><br></div><div>-------------------</div><div><br></div><div>Memory: 7.8 GiB</div><div>Processor:: Intel® Core™ i5-2540M CPU @ 2.60GHz × 4</div><div><br></div><div>

File to compress: 1.9G</div><div><br></div><div>xz -f -k -e -9 --check=crc32 (current configuration)</div>
<div>Memory: 673Mb</div><div><div>real    6m37.170s</div><div>user    6m35.389s</div><div>sys     0m0.884s</div></div><div>Compressed file size: 3.4Mb</div><div><br></div><div><div>xz -f -k -e -9 -T 4 --check=crc32</div>

<div>Memory: Cannot allocate memory</div></div><div><br></div><div><div>xz -f -k -e -8 -T 4 --check=crc32</div><div>Memory: 1.8G</div></div><div><div>real    3m24.462s</div><div>user    12m8.502s</div><div>sys     0m2.180s</div>

</div><div>Compressed file size: 3.4Mb</div><div><br></div><div><div><div>xz -f -k -T 4 --check=crc32 (-e defaults to -6)</div><div>Memory: 471Mb</div></div><div><div>real    1m9.265s</div><div>user    4m8.972s</div><div>

sys     0m0.944s</div></div><div>Compressed file size: 3.4Mb</div></div><div><br></div><div>So my conclusion would be to use the default -e -6 with -T 4. </div><div><br></div><div>@g</div><div>
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