NAME

       xbstream - Percona xbstream Documentation

       To  support  simultaneous  compression  and  streaming, a new custom streaming format called xbstream was
       introduced to Percona XtraBackup in addition to the TAR  format.  That  was  required  to  overcome  some
       limitations  of  traditional  archive  formats such as tar, cpio and others which did not allow streaming
       dynamically generated files, for example dynamically compressed files. Other advantages of xbstream  over
       traditional  streaming/archive  format  include  ability  to stream multiple files concurrently (so it is
       possible to use streaming in the xbstream format together with the --parallel option)  and  more  compact
       data storage.

       This utility has a tar-like interface:

          • with  the  -x  option  it extracts files from the stream read from its standard input to the current
            directory unless specified otherwise with the -c option. Support for parallel  extraction  with  the
            --parallel option has been implemented in Percona XtraBackup 2.4.7.

          • with the -c option it streams files specified on the command line to its standard output.

          • with  the  --decrypt=ALGO  option specified xbstream will automatically decrypt encrypted files when
            extracting input stream. Supported values for this option are: AES128, AES192,  and  AES256.  Either
            --encrypt-key  or  --encrypt-key-file  options  must be specified to provide encryption key, but not
            both. This option has been implemented in Percona XtraBackup 2.4.7.

          • with the --encrypt-threads  option  you  can  specify  the  number  of  threads  for  parallel  data
            encryption. The default value is 1. This option has been implemented in Percona XtraBackup 2.4.7.

          • the  --encrypt-key  option is used to specify the encryption key that will be used. It can't be used
            with --encrypt-key-file option because they are mutually exclusive. This option has been implemented
            in Percona XtraBackup 2.4.7.

          • the --encrypt-key-file option is used to specify the file that contains the encryption key. It can't
            be used with --encrypt-key option.  because they  are  mutually  exclusive.  This  option  has  been
            implemented in Percona XtraBackup 2.4.7.

       The  utility  also  tries  to  minimize  its  impact  on  the  OS  page  cache  by  using the appropriate
       posix_fadvise() calls when available.

       When compression is enabled with xtrabackup all data is being compressed, including the  transaction  log
       file  and  meta  data  files,  using  the  specified  compression algorithm. The only currently supported
       algorithm is quicklz.

       The resulting files have the qpress archive format, i.e., every  *.qp  file  produced  by  xtrabackup  is
       essentially  a one-file qpress archive and can be extracted and uncompressed by the qpress file archiver.
       This means that there is no need to decompress entire backup to restore a single table as with tar.gz.

       To decompress individual files, run xbstream with the --decompress option. You may control the number  of
       threads used for decompressing by passing the --decompress-threads option.

       Also,  files  can be decompressed using the qpress tool that can be downloaded from here. Qpress supports
       multi-threaded decompression.

AUTHOR

       Percona LLC and/or its affiliates

COPYRIGHT

       2009-2022, Percona LLC and/or its affiliates

8.0                                               Nov 30, 2023                                       XBSTREAM(1)