outgoing: rework the handling of the `missingroots` case to be faster
The previous implementation was slow, to the point it was taking a significant
amount of `hg bundle --type none-streamv2` call. We rework the code to compute
the same value much faster, making the operation disappear from the `hg bundle
--type none-streamv2` profile. Someone would remark that producing a streamclone
does not requires an `outgoing` object. However that is a matter for another
day. There is other user of `missingroots` (non stream `hg bundle` call for
example), and they will also benefit from this rework.
We implement an old TODO in the process, directly computing the missing and
common attribute as we have most element at hand already.
### benchmark.name = hg.command.bundle
# bin-env-vars.hg.flavor = default
# bin-env-vars.hg.py-re2-module = default
# benchmark.variants.revs = all
# benchmark.variants.type = none-streamv2
## data-env-vars.name = heptapod-public-2024-03-25-zstd-sparse-revlog
before: 7.750458
after: 6.665565 (-14.00%, -1.08)
## data-env-vars.name = mercurial-public-2024-03-22-zstd-sparse-revlog
before: 0.700229
after: 0.496050 (-29.16%, -0.20)
## data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog
before: 346.508952
after: 316.749699 (-8.59%, -29.76)
## data-env-vars.name = pypy-2024-03-22-zstd-sparse-revlog
before: 3.401700
after: 2.915810 (-14.28%, -0.49)
## data-env-vars.name = tryton-public-2024-03-22-zstd-sparse-revlog
before: 1.870798
after: 1.461583 (-21.87%, -0.41)
note: this whole `missingroots` of outgoing has a limited number of callers and
could likely be replace by something simpler (like taking an explicit
"missing_revs" set for example). However this is a wider change and we focus on
a small impact, quick rework that does not change the API for now.
#require no-windows
$ . "$TESTDIR/remotefilelog-library.sh"
$ hg init master
$ cd master
$ cat >> .hg/hgrc <<EOF
> [remotefilelog]
> server=True
> EOF
$ echo x > x
$ hg commit -qAm x
$ cd ..
$ hgcloneshallow ssh://user@dummy/master shallow -q
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
$ cd shallow
$ cat >> $TESTTMP/get_file_linknode.py <<EOF
> from mercurial import node, registrar, scmutil
> cmdtable = {}
> command = registrar.command(cmdtable)
> @command(b'debug-file-linknode', [(b'r', b'rev', b'.', b'rev')], b'hg debug-file-linknode FILE')
> def debug_file_linknode(ui, repo, file, **opts):
> rflctx = scmutil.revsingle(repo.unfiltered(), opts['rev']).filectx(file)
> ui.status(b'%s\n' % node.hex(rflctx.ancestormap()[rflctx._filenode][2]))
> EOF
$ cat >> .hg/hgrc <<EOF
> [ui]
> interactive=1
> [extensions]
> strip=
> get_file_linknode=$TESTTMP/get_file_linknode.py
> [experimental]
> evolution=createmarkers,allowunstable
> EOF
$ echo a > a
$ hg commit -qAm msg1
$ hg commit --amend 're:^$' -m msg2
$ hg commit --amend 're:^$' -m msg3
$ hg --hidden log -G -T '{rev} {node|short}'
@ 3 df91f74b871e
|
| x 2 70494d7ec5ef
|/
| x 1 1e423846dde0
|/
o 0 b292c1e3311f
$ hg debug-file-linknode -r 70494d a
df91f74b871e064c89afa1fe9e2f66afa2c125df
$ hg --hidden strip -r 1 3
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
saved backup bundle to $TESTTMP/shallow/.hg/strip-backup/df91f74b871e-c94d67be-backup.hg
$ hg --hidden log -G -T '{rev} {node|short}'
o 1 70494d7ec5ef
|
@ 0 b292c1e3311f
Demonstrate that the linknode points to a commit that is actually in the repo
after the strip operation. Otherwise remotefilelog has to search every commit in
the repository looking for a valid linkrev every time it's queried, such as
during push.
$ hg debug-file-linknode -r 70494d a
70494d7ec5ef6cd3cd6939a9fd2812f9956bf553