Commits
- Commit:
e44d939152693c16e95d2855b539ad6b30e81b15
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
revert object enumeration in got-read-pack for now; needs more work
This implementation marked commits and trees as enumerated before all trees
which they depend on were enumerated. This behaviour leads to incomplete
pack files when a tree is only partially packed and got-read-pack hits
a missing tree entry as a result. The algorithm must be reworked such
that packed leave nodes are marked enumerated first, then bubble-up.
Found by op@
- Commit:
9f4f302a43f7e186910d59f9dbe0f839b6f2d565
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
free id and path in load_packed_tree_ids() on error, else they would leak
pointed out by op@
- Commit:
cee6a7ea556f9f3ae0f50df959c2acd8cb59bf80
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
implement object enumeration support in got-read-pack
ok op@
- Commit:
ce2bf7b7c9058374563c6db8608dbab9df2bba7d
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
fix a bug in findwixt() which caused pack files with missing parent commits
The 'nskip' variable is supposed to reflect commits which are waiting on
the queue and have the 'skip' color. Only increment 'nskip' when adding
such commits to the queue.
Problem observed with got send -T and a tag pointing to a deleted branch.
Test to reproduce the bug written by op@.
- Commit:
d6a28ffe187127e3247254d7e242bb52d66eb26b
- From:
- Omar Polo <op@omarpolo.com>
- Date:
use random seeds for murmurhash2
change the three hardcoded seeds to fresh ones generated on demand via
arc4random. Suggested/fixed by and ok stsp@
- Commit:
17cfdba68dcb4432269af930abb1f9fb9ee48e97
- From:
- Omar Polo <op@omarpolo.com>
- Date:
include header
- Commit:
411cbec1f714f639184814306c5c88454521e289
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
shrink struct got_pack_meta a bit by removing the have_reused_delta flag
This flag can be expressed as m->reused_delta_offset != 0 because all
deltas in valid pack files will be written at a non-zero offset.
We allocate a huge number of these structs during packing, so every
little bit helps.
- Commit:
adb4bbb29d6a1407355e47e71716ca7f40c6dd67
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
reduce the amount of memory used for caching deltas during deltification
With files sorted properly for deltification we produce better deltas
but end up consuming more memory and risk running into OpenBSD ulimits
during packing. To compensate, reduce the threshold for the amount of
delta data we store in memory, spooling more deltas into the cache file.
ok op@
- Commit:
f8174ca59ba426ea9c475fd15d2db770f8595b5e
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
store a path hash instead of a verbatim path in pack meta data
This reduces memory use by gotadmin pack. The goal is to sort files
which share a path next to each other for deltification. A hash of
the path is good enough for this purpose and consumes less memory
than a verbatim copy of the path. Git does something similar.
ok op@
- Commit:
3e6ceea0bd8a65737eb2231ce18d0e591dfb92ff
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
fix paths stored in pack meta data, improving file deltification
The old code was broken and stored an empty path or filenames, instead
of a repository-relative path. Which means we didn't sort files for
deltification as was intended.
Fixing this provides much better deltas in large pack files written by
gotadmin pack -a. In my test case, pack size changed from 2GB to 1.5GB.
ok op@
- Commit:
17259bfa94068499f61aec3129c47ae2671bd531
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
plug a small memleak on error in got_pack_create()
- Commit:
e93fb944fe7b32d96fafd4726043a28062563b54
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
map delta cache file into memory if possible while writing a pack file
with a fix from + ok op@
- Commit:
dc3fe1bf10950c200037f0198f2445ea176f8cc3
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
fix load_object_ids() such that packing tags works if zero commits are packed
reported by jrick and op
- Commit:
fae7e03842e8618973f4d4910a86a52d881ab2ab
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
run the search for deltas to reuse in got-read-pack
This significantly speeds up the deltification step of packing by
avoiding imsg traffic. gotadmin no longer requests individual raw
deltas from got-read-pack to check whether it can reuse them.
Instead, got-read-pack obtains a list of objects we want to pack,
and hands back the list of all deltas in its pack file which can be
reused. Messages are now batched such that imsg buffers are filled
as much as possible.
Another advantage is that deltas we are not going to reuse will
no longer be written to the delta cache file, saving disk space.
Before this patch, any raw delta candidate was written to the
delta cache file by got-read-pack, and the decision whether to
reuse the delta happened afterwards in the gotadmin process.
Code for reading individual raw deltas is now unused and could be
removed at some point.
ok op@
- Commit:
2f8438b006e9015401b93f55cea57b36b021ce56
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
avoid 'remove unused' loop by storing excluded objects in a separate set
ok op@
- Commit:
f5e78e05ae4eb8c5e5909841ee696fa5b6d0dfea
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
avoid loop over the ID set which removes objects IDs with reused deltas
ok op@
- Commit:
2d9e6abf243a0a1895786fa9002b28d69a0f6fea
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
store deltas in compressed form while packing, both in memory and cache file
This reduces memory and disk space consumption during packing.
with tweaks + memleak on error fix from op@
ok op@
- Commit:
611e8e319eae000b4d691f6c188af95e4de294a7
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
avoid subtraction of values larger than int in qsort(3) comparison callbacks
tweak + ok tb@
- Commit:
d7b5a0e827bb38e5c8502f0ba8d7838fedaba19b
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
inline struct got_object_id in struct got_object_qid
Saves us from doing a malloc/free call for every item on the list.
ok op@
- Commit:
cbc287dcbb29ad321dca5cd14c31998279205243
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
reimplement object-ID set data structure on top of a hash table
Siphash suggested by jrick as a better alternative to murmurhash
for this use case.
with small fixes from and ok op@
- Commit:
70f8f24dc5b689abd6265a71e787dfef79ba40cf
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
speed up initial stage of packing by adding a "skip" commit color
The skip color marks boundary commits and their ancestors. Boundary commits
are reachable both via references which we want to exclude from the pack,
and via references which we want to include in the pack.
We continue processing commit history up to the point we are left with only
skip commits on the queue. This can speed up findtwixt() significantly and
avoids wrong results produced by the old algorithm which made no distinction
between "drop" and "skip".
This idea was first implemented by Michael Forney for git9:
https://git.9front.org/plan9front/plan9front/2e47badb88312c5c045a8042dc2ef80148e5ab47/commit.html
Michael's log message for git9 is reproduced below:
git/query: refactor graph painting algorithm (findtwixt, lca)
We now keep track of 3 sets during traversal:
- keep: commits we've reached from head commits
- drop: commits we've reached from tail commits
- skip: ancestors of commits in both 'keep' and 'drop'
Commits in 'keep' and/or 'drop' may be added later to the 'skip' set
if we discover later that they are part of a common subgraph of the
head and tail commits.
From these sets we can calculate the commits we are interested in:
lca commits are those in 'keep' and 'drop', but not in 'skip'.
findtwixt commits are those in 'keep', but not in 'drop' or 'skip'.
The "LCA" commit returned is a common ancestor such that there are no
other common ancestors that can reach that commit. Although there can
be multiple commits that meet this criteria, where one is technically
lower on the commit-graph than the other, these cases only happen in
complex merge arrangements and any choice is likely a decent merge
base.
Repainting is now done in paint() directly. When we find a boundary
commit, we switch our paint color to 'skip'. 'skip' painting does
not stop when it hits another color; we continue until we are left
with only 'skip' commits on the queue.
This fixes several mishandled cases in the current algorithm:
1. If we hit the common subgraph from tail commits first (if the tail
commit was newer than the head commit), we ended up traversing the
entire commit graph. This is because we couldn't distinguish
between 'drop' commits that were part of the common subgraph, and
those that were still looking for it.
2. If we traversed through an initial part of the common subgraph from
head commits before reaching it from tail commits, these commits
were returned from findtwixt even though they were also reachable
from tail commits.
3. In the same case as 2, we might end up choosing an incorrect
commit as the LCA, which is an ancestor of the real LCA.
- Commit:
bb6672b6aba1cb45a10d52bec828e68379e9ad61
- From:
- Theo Buehler <tb@openbsd.org>
- Date:
make sure callers of got_object_idset_add() free data.
- Commit:
fbafdecfb2616668a85d20ef641764749a229f7a
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
revert 03c03172 "drop a commit right away if it matches an excluded commit"
This change resulted in a full history walk even when no objects will
be added to the pack file. Fix this regression by reverting the change.
- Commit:
14dbbf48885998b6db226d20b27b77b094ceea23
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
for clarity, move the coloring loop from findtwixt() into a separate function
- Commit:
1d765da334af12ddd26b666c0294e0d39f45cbdf
- From:
- Stefan Sperling <stsp@stsp.name>
- Date:
remove a pointless object-id dup/free dance in findtwixt()