Allows you to specify options for process of creating or updating archive.
Specifies compression level. There are 6 levels of compression:
| Value | Meaning |
|---|---|
| Store | Files will be copied to archive without compression. |
| Fastest | Fastest compression. |
| Fast | Fast compression. |
| Normal | Compression with balanced settings. |
| Maximum | It can give more compression ratio than Normal level. But it can be slower and it can require more memory. |
| Ultra | It can give more compression ratio than Maximum level. But it can be slower and it can require more memory. |
Specifies compression method. Each archive format can have its own compression methods:
| Method | Description |
|---|---|
| LZMA | Default compression method of 7z format. It provides high compression ratio and very fast decompression. |
| PPMd | Dmitry Shkarin's PPMdH algorithm with small changes. Usually it provides high compression ratio and high speed for text files. |
| BZip2 | Standard compression method based on BWT algorithm. Usually it provides high speed and pretty good compression ratio for text files. |
| Deflate | Standard compression method of ZIP and GZip formats. Compression ratio is not too high. But it provides pretty fast compressing and decompressing. Deflate method supports only 32 KB dictionary. |
| Deflate64 | Modified version of Deflate algorithm with bigger dictionary (64KB). |
Estimated 7-Zip performance and memory requirements for AMD Athlon 64 X2 3800+:
| Method | Level | Dictionary Size | Compressing Speed | Decompressing Speed | Memory for Compressing | Memory for Decompressing |
|---|---|---|---|---|---|---|
| LZMA | fastest | 64 KB | 4.5 MB/s | 15 MB/s | 3 MB | 3 MB |
| fast | 1 MB | 3 MB/s | 10 MB | 3 MB | ||
| normal | 4 MB | 2.2 MB/s | 54 MB | 6 MB | ||
| maximum | 16 MB | 1.8 MB/s | 192 MB | 18 MB | ||
| ultra | 64 MB | 1.6 MB/s | 709 MB | 66 MB | ||
| PPMD | fast | 4 MB | 1.4 MB/s | 6 MB | ||
| normal | 24MB | 1.2 MB/s | 26 MB | |||
| maximum | 64 MB | 1.0 MB/s | 66 MB | |||
| ultra | 192 MB | 0.9 MB/s | 194 MB | |||
| Deflate | normal | 32 KB | 3.5 MB/s | 40 MB/s | 3 MB | 2 MB |
| maximum | 1.5 MB/s | 4MB | ||||
| ultra | 0.4 MB/s | |||||
| BZip2 | normal | 900 KB | 3 MB/s | 16 MB/s | 20 MB | 7 MB |
| maximum | 1.2 MB/s | |||||
| ultra | 0.4 MB/s | |||||
Specifies Dictionary size for compression method.
Usually higher Dictionary size gives more compression ratio. But compressing can be slower and it can require more memory.
Memory (RAM) usage for LZMA compressing is about 11 times more than dictionary size. Memory usage for LZMA decompressing is close to value of dictionary size. Memory usage for PPMd compressing and decompressing is almost equal to dictionary size.
Specifies the length of words, which will be used to find identical sequences of bytes for compression.
Usually for LZMA and Deflate big Word size gives a little bit better compression ratio and slower compression process. Big Word size parameter can significantly increase compression ratio in case when files contain long identical sequences of bytes. For PPMd Word size has big meaning. It strongly affects both compression ratio and compression/decompression speed.
Enables or disables solid mode. In solid mode all files will be compressed as one continuous data stream. Usually compressing to solid archive improves compression ratio. You can use this option only for 7z archives. With current version of 7z you can update existing archives only when solid mode is switched off. Updating solid archives also is not supported in current version.
Enables or disables Multi-threading compression mode. In Multi-threading mode, 7-Zip will use two threads for compressing. It can speed up compressing speed up to 50-80% on Multi-Processor systems or up to 30% on Pentium 4 with Hyper-Threading.
Provides a space for you to specify parameters for compressing. Look to -m (Method) switch description for more details. You mustn't specify -m prefix (as in -m switch) in this dialog box.
Examples
0=PPMd
uses PPMd method for compressing files.
0=bcj2 1=lzma:d23 2=lzma 3=lzma b0:1 b0s1:2 b0s2:3
uses BCJ2 filter (for x86 executables) and LZMA.
Specifies update mode:
| Value | Meaning |
|---|---|
| Add and replace files | Add all specified files to the archive. |
| Update and add files | Update older files in the archive and add files that are new to the archive. |
| Freshen existing files | Update specified files in the archive that are older than the selected disk files. |
| Synchronize files | Replace specified files only if added files are newer. Always add those files, which are not present in the archive. Delete from archive those files, which are not present on the disk. |
Specifies compression options:
| Option | Meaning |
|---|---|
| Create SFX archive | Creates self-extracting archive. You can use this option only for 7z archives. Look to -sfx (Create SFX archive) switch description for more details about SFX modules. |
Specifies password for encrypting.
{Size}[b | k | m | g]
Specifies volumes sizes in Bytes, Kilobytes (1 Kilobyte = 1024 bytes), Megabytes (1 Megabyte = 1024 Kilobytes) or Gigabytes (1 Gigabyte = 1024 Megabytes). if you specify only {Size}, 7-zip will treat it as bytes. It's possible to specify several values. Example:
10k 15k 2m
First volume will be 10 KB, second will be 15 KB, and all others will be 2 MB.