The compressalways option specifies whether to continue compressing an object if it grows during compression, or resend the object, uncompressed. This option is valid when client compression is enabled by the compression option.
The compressalways option is used with the archive, incremental, and selective commands. This option can also be defined on the server. If this option is set to yes, the default value, files compression continues even if the file size increases. To stop compression if the file size grows, and resend the file uncompressed, specify compressalways no. This option controls compression only if the administrator specifies that the client node determines the selection. To reduce the impact of repeated compression attempts if the compressed file is larger than the original, specify compressalways yes.
To prevent unsuccessful compression attempts, you can list files that cannot be compressed on one or more client exclude.compression statements. Exclude files that contain graphics; even exclude word-processing files if they contain embedded graphics. Also, exclude audio files, video files, files that are already encrypted, and files that are saved in an archive format, such as .jar files, .zip files, and other compressed file formats.
Using Tivoli® Storage Manager client compression and encryption for the same files is valid. The client first compresses the file data and then encrypts it, so that there is no loss in compression effectiveness that is caused by encryption, and encryption is faster if there is less data to encrypt.
exclude.compression ?:\...\*.gif
exclude.compression ?:\...\*.jpg
exclude.compression ?:\...\*.zip
exclude.compression ?:\...\*.mp3
exclude.compression ?:\...\*.cab
exclude.compression ?:\...\*.aes
exclude.compression ?:\...\*.rsaThe preferred setting is compressalways yes, and then use exclude.compression statements to omit files that cannot be compressed.