1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
|
[[!meta title="DRAFT: Roadmap for FORMET GREEN ALBATROSS"]]
This is a DRAFT roadmap for the new repository format (GREEN
ALBATROSS) to become the default format in Obnam. Feedback on this
roadmap is welcome via the obnam-devel mailing list.
Note that only things that affect the new repository format are
relevant for this roadmap. All other bugs or features are off-topic
and will not be included.
Success criteria for being done with the new format
========================================================================
* All major operations need to be tolerably fast, and run in 4 GiB of
RAM. The test data set is to be the snapshot of almost 5 TiB data
from my own file server. The backup repository should use encryption
and compression.
- backup
- forget
- restore (or possibly verifyy, to avoid needing another 5 TiB space)
- fsck
* Obnam supports Attic-style chunking (lowest N bits of weak checksum
means chunk ends), and things are still tolerably fast.
* The manual needs to be updated to cover all GA things and needs to
have a comparison between 6 and GA, and also advice for converting
to the new format ("start over" is sufficient, though a conversion
tool would be nice).
* The obnam.org website needs to be reviewed, and any design docs
updated.
* At least three months needs to have passed of actively asking Obnam
users to use GA, without showstopper bugs being reported.
* No known need to change the new repository format.
Roadmap
========================================================================
This is the rough order of things that I know needs doing. There are
certainly things missing from the list, reality always wins over my
most careful planning.
* Add new benchmarks for all the success criteria. All the operations
listed above should be benchmarked. Then analyze results and make
any optimizations needed.
* Add Attic-style chunking. These chunks are not of fixed size at
fixed positions in the files. This matters to the repository format
because there may be lots more chunks, depending on settings, and
the format needs to handle that.
* Add sparse file handling to GA. Sparse files are not used by
everyone, but those that do, really want them. Obnam currently
doesn't handle them optimally and has not way of representing them
in the repository except as long sequences of all-bits-zero bytes
* Make sure Obnam handles the case of an unknown username or group
name of a file (only numeric uid or gid known). This is important
when it's not feasible to get the user/group name from an SFTP
server. This affects the repository format only a little, but it
needs to allow storing a value to represent "not known", and all
code needs to be to deal with that.
* Review obnam.org website and make any necessary updates.
* Review Obnam manual and make any necessary updates. Co-ordinate with
translators to get non-English versions of the manual to also be
updated.
* Make an Obnam release with a beta level version of GA, and ask
people to use it and report results.
|
