| Versions tested: | 0.34, 0.35b, 0.39, 1.1 |
| Optimal parameters: | L3 |
| Links: | http://www.quicklz.com/ |
| Authors: | Lasse Reinhold |
| Algorithms: | LZ |
| Notable peformances: | Application3, Image1, Pitches1, Qualifying1, Qualifying2 |
qpress is a portable file archiver designed to utilize fast storage systems to their max. It supportsthe program website April 13, 2009
- multiple cores, reaching upto 1.1 Gbyte/s in-memory compression on a quad core Xeon
- 64-bit file sizes and tested with terabyte sized archives containing millions of files and directories
- pipes and redirection and *nix-like behaviour for scripting and flexibility
- Adler32 checksums to ensure that decompressed data has not been corrupted
- data recovery of damaged archives with 64 Kbyte grannularity
- unbuffered disk I/O (Windows only) to prevent disk cache of other applications from being flushed
(Have info that should be added here? E-mail.)
We test the program with TAR mode to avoid time overhead accessing multiple files.
| Ver | Rating | CPR | DPR | S.E. | R.E. | Ratio | C. kB/s | D. kB/s | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| L1 | ||||||||||||
| 0.34 | 1 | 3 | 0 | 702 | 0 | 1.970 | 570184 | 505916 | ||||
| 0.35b | 1 | -5.1% | 1.970 | 0% | 537203 | -5.8% | 483161 | -4.5% | ||||
| 0.39 | 1 | +1.8% | 1.970 | 0% | 531620 | -1.0% | 504411 | +4.4% | ||||
| 1.1 | 1 | +1.5% | 1.970 | 0% | 541536 | +1.9% | 509515 | +1.0% | ||||
| L2 | ||||||||||||
| 0.34 | 4 | 7 | 0 | 710 | 0 | 2.111 | 326381 | 436264 | ||||
| 0.35b | 4 | -3.0% | 2.111 | 0% | 319837 | -2.0% | 417554 | -4.3% | ||||
| 0.39 | 4 | +5.1% | 2.111 | 0% | 318384 | -0.5% | 473089 | +13% | ||||
| 1.1 | 4 | -0.1% | 2.111 | 0% | 318920 | +0.2% | 470877 | -0.5% | ||||
| L3 | ||||||||||||
| 0.34 | 5 | 6 | 2 | 489 | 0 | 2.209 | 125172 | 549946 | ||||
| 0.35b | 5 | -2.9% | 2.209 | 0% | 123664 | -1.2% | 498404 | -9.4% | ||||
| 0.39 | 5 | +9.3% | 2.209 | 0% | 134739 | +9.0% | 553155 | +11% | ||||
| 1.1 | 5 | +0.4% | 2.209 | 0% | 134829 | +0% | 559299 | +1.1% | ||||