COMPRESSION RATIO
-wimlib (and wimlib-imagex) can create XPRESS, LZX, or LZMS compressed WIM archives.
-The following tables compare the compression ratio and performance for creating
-a compressed x86_64 Windows PE image. Note: these timings were done on Windows
-so that the times would be fully comparable; however, wimlib may have even
-better performance on other operating systems such as Linux. Timings were done
-with 2 CPUs available, both of which automatically are used by wimlib for both
-XPRESS and LZX, and also by imagex.exe but apparently only for LZX. Results for
-LZMS compression are excluded because the creation of LZMS compressed WIM
-archives is not yet recommended.
+wimlib (and wimlib-imagex) can create XPRESS, LZX, or LZMS compressed WIM
+archives. The following tables compare the compression ratio and performance
+for creating a compressed x86_64 Windows PE image with XPRESS and LZX. Note:
+these timings were done on Windows so that the times would be fully comparable;
+however, wimlib may have even better performance on other operating systems such
+as Linux. Timings were done with 2 CPUs available, both of which automatically
+are used by wimlib for both XPRESS and LZX, and also by imagex.exe but
+apparently only for LZX.
Table 1. WIM size
and "LZX", instead of "fast" and "maximum", respectively.
.IP ""
As of wimlib v1.6.0, a third compression type, "recovery" or "LZMS", is also
-available. Its use is not recommended because other than wimlib itself, as of
-Windows 8 it is only compatible with WIMGAPI and Windows Setup (not even ImageX
-or Dism). Furthermore, wimlib's LZMS compressor is currently less well
-optimized than its LZX compressor. However, LZMS is the compression algorithm
-used in packed resources created if the \fB--pack-streams\fR option is
-specified.
+available. Its use is generally not recommended because other than wimlib
+itself, as of Windows 8 it is only compatible with WIMGAPI and Windows Setup
+(not even ImageX or Dism). However, LZMS is the compression algorithm used in
+packed resources created if the \fB--pack-streams\fR option is specified.
.TP
\fB--compress-slow\fR
Spend even more time compressing the data to achieve a very slightly better
/* This a compressor for the LZMS compression format. More details about this
* format can be found in lzms-decompress.c.
*
- * This is currently an unsophisticated implementation that is fast but does not
- * attain the best compression ratios allowed by the format.
+ * NOTE: this compressor currently does not code any delta matches.
*/
#ifdef HAVE_CONFIG_H