1XBSTREAM(1)                   Percona XtraBackup                   XBSTREAM(1)
2
3
4

NAME

6       xbstream - Percona xbstream Documentation
7
8       To support simultaneous compression and streaming, a new custom stream‐
9       ing format called xbstream was introduced to Percona XtraBackup in  ad‐
10       dition  to  the  TAR format. That was required to overcome some limita‐
11       tions of traditional archive formats such as tar, cpio and others which
12       did not allow streaming dynamically generated files, for example dynam‐
13       ically compressed files. Other advantages of xbstream over  traditional
14       streaming/archive  format include ability to stream multiple files con‐
15       currently (so it is possible to use streaming in  the  xbstream  format
16       together with the --parallel option) and more compact data storage.
17
18       This utility has a tar-like interface:
19
20          • with the -x option it extracts files from the stream read from its
21            standard input to the current directory unless specified otherwise
22            with  the  -c  option.  Support  for  parallel extraction with the
23            --parallel option  has  been  implemented  in  Percona  XtraBackup
24            2.4.7.
25
26          • with  the -c option it streams files specified on the command line
27            to its standard output.
28
29          • with the --decrypt=ALGO option specified xbstream  will  automati‐
30            cally  decrypt  encrypted files when extracting input stream. Sup‐
31            ported values for this option are: AES128, AES192, and AES256. Ei‐
32            ther --encrypt-key or --encrypt-key-file options must be specified
33            to provide encryption key, but not both. This option has been  im‐
34            plemented in Percona XtraBackup 2.4.7.
35
36          • with  the  --encrypt-threads  option you can specify the number of
37            threads for parallel data encryption. The default value is 1. This
38            option has been implemented in Percona XtraBackup 2.4.7.
39
40          • the  --encrypt-key  option  is  used to specify the encryption key
41            that will be used. It can't be used with --encrypt-key-file option
42            because  they  are mutually exclusive. This option has been imple‐
43            mented in Percona XtraBackup 2.4.7.
44
45          • the --encrypt-key-file option is used to  specify  the  file  that
46            contains  the  encryption key. It can't be used with --encrypt-key
47            option.  because they are mutually exclusive. This option has been
48            implemented in Percona XtraBackup 2.4.7.
49
50       The  utility  also tries to minimize its impact on the OS page cache by
51       using the appropriate posix_fadvise() calls when available.
52
53       When compression is enabled with xtrabackup  all  data  is  being  com‐
54       pressed,  including the transaction log file and meta data files, using
55       the specified compression algorithm. The only currently supported algo‐
56       rithm is quicklz.
57
58       The  resulting  files  have the qpress archive format, i.e., every *.qp
59       file produced by xtrabackup is essentially a  one-file  qpress  archive
60       and can be extracted and uncompressed by the qpress file archiver. This
61       means that there is no need to decompress entire backup  to  restore  a
62       single table as with tar.gz.
63
64       To  decompress individual files, run xbstream with the --decompress op‐
65       tion. You may control the number of threads used for  decompressing  by
66       passing the --decompress-threads option.
67
68       Also, files can be decompressed using the qpress tool that can be down‐
69       loaded from here. Qpress supports multi-threaded decompression.
70

AUTHOR

72       Percona LLC and/or its affiliates
73

75       2009-2021, Percona LLC and/or its affiliates
76
77
78
79
808.0                              May 31, 2021                      XBSTREAM(1)
Impressum