I'm not entirely happy with using a trailing / on a "file" entry for
transferring a treemanifest. We've discussed putting some flags on
each file header[0], but I'm unconvinced that's actually any better:
if we were going to add another feature to the cg format we'd still be
doing a version bump anyway to cg4, so I'm inclined to not spend time
coming up with a more sophisticated format until we actually know what
the next feature we want to stuff in a changegroup will be.
Test changes outside test-treemanifest.t are only due to the new CG3
bundlecap showing up in the wire protocol.
Many thanks to adgar@google.com and martinvonz@google.com for helping
me with various odd corners of the changegroup and treemanifest API.
0: It's not hard refactoring, nor is it a lot of work. I'm just
disinclined to do speculative work when it's not clear what the
customer would actually be.
In the fastpathlinkrev case, lookupmflinknode was a very complicated
way of saying mfs.__getitem__, so let's just get that case out of our
way so it's easier to understand what's going on.
The old code gathered the list of all files that changed anywhere in
history and then gathered changed file nodes by walking the entirety
of each manifest to be sent in order to gather changed file
nodes. That's going to be unfortunate for narrowhg, and it's already
inefficient for medium-to-large repositories.
Timings for bundle --all on my hg repo, tested with hgperf:
Before:
! wall 23.442445 comb 23.440000 user 23.250000 sys 0.190000 (best of 3)
After:
! wall 20.272187 comb 20.270000 user 20.190000 sys 0.080000 (best of 3)
An upcoming change for exchanging treemanifest data will need to
update the repository capabilities, which we should only do if the
repository was empty before we started applying this changegroup. In
the future we will probably need a strategy for upgrading to
treemanifest in requires during a pull (I'm assuming at some point
we'll make it possible to have a flag day to enable treemanifests on
an existing history.)
The previous changeset is a simpler way of fixing issue4934 without changing the
spirit of the code. We can remove the dual call to 'delayupdate' but we keep the
tests to show that the issue is still fixed.
The 'prechangegroup' interfere with 'delayupdate' logic because it trigger the
one time call of 'changelog._writepending' (see issure4934). There is no reason
not to call that hook before setting up 'delayupdate' so we move the call a bit
earlier to avoid interference.
The try finally is here to ensure we release the just-created transaction.
Therefore we should not do half a dozen operations before actually entry the try
scope.
We need to call delayupdate again after writing to the changelog.
Otherwise the prechangegroup hook consumes the delayupdate subscription and
future hooks don't see the pending changes (see issue 4934 for more details).
Adds a test that triggers the prechangegroup hook before the pretxnchangegroup
hook and verifies that the output of pretxnchangegroup doesn't change.
This patch centralizes passing HG_PENDING to external hook process
into '_exthook()'. To make in-memory changes visible to external hook
process, this patch does:
- write (or schedule to write) in-memory dirstate changes, and
- set HG_PENDING environment variable, if:
- a transaction is running, and
- there are in-memory changes to be visible
This patch tests some commands with some hooks, because transaction
activity of a same hook differs from each other ("---": "not tested").
======== ========= ========= ============
command preupdate precommit pretxncommit
======== ========= ========= ============
unshelve o --- ---
backout x --- ---
import --- o o
qrefresh --- x o
======== ========= ========= ============
Each hooks are examined separately to prevent in-memory changes from
being visible to external process accidentally by side effect of hooks
previously invoked.
I'm about to add a cg3, and it seems prudent to annotate what formats
support what features. It strikes me that we may want to consider
moving to a more feature-oriented model in the future, but we'll see
how that looks in a little while I guess.
I'm not sure what to do abstraction-wise here. It might be more
sensible to make a memoryrepo that could apply a bundle in-memory and
then we could make the changegroup data be strictly an applyable
stream, but that's an idea for Later.
The current setup requires to pass both a packer and, optionally, the version
of the unpacker. This is confusing and error prone as the two value cannot
mismatch. Instead, we simply grab the version from the packer. This fixes a bug
where requesting a cg2 from 'hg bundle' were reported as changegroup 1.
I should have caught that in the initial changeset but I missed it somehow.
The home of 'Abort' is 'error' not 'util' however, a lot of code seems to be
confused about that and gives all the credit to 'util' instead of the
hardworking 'error'. In a spirit of equity, we break the cycle of injustice and
give back to 'error' the respect it deserves. And screw that 'util' poser.
For great justice.
The current writebundle function do two things:
- taking a changegroup-packer instance and storing it into a valid bundle with
proper header.
- creating a temporary or requested file to store that bundle
We would like to make it easier to forward bundle stream directly from a remote
peer to a file, so we split the two logic to be able to skip the one about
building a valid bundle (the remote is already sending one).
For some obscure reasons (probably upsetting a Greek goddess),
getchangegroup did not had a 'version' argument to control the changegroup
version. We fixes this to allow cg02 to be used with 'hg bundle' in the future.
For some obscure reasons (probably upsetting a Greek goddess),
getlocalchangegroup did not have a 'version' argument to control the
changegroup version. We fix this to allow cg02 to be used with 'hg
bundle' in the future.
Bundle2 compression is more complex than the bundle1 one. Therefore it
is handled by the bundler itself. Moreover, on-disk bundle2 will
probably have a large number of flavors so simply adding a new "format"
for it does not seems the way to go.
This will be used in the next changeset to compress bundle2 strip backup.
For "space saving", bundle1 "strip" the first two bytes of the BZ stream since
they always are 'BZ'. So the current code boostrap the uncompressor with 'BZ'.
This hack is impractical in more generic case so we move it in a dedicated
"decompression".
Before this patch, addchangegroup() would walk the changelog and compute
the set of seen files between applying changesets and applying
manifests. When cloning large repositories such as mozilla-central,
this consumed a non-trivial amount of time. On my MBP, this walk takes
~10s. On a dainty EC2 instance, this was measured to take ~125s! On the
latter machine, this delay was enough for the Mercurial server to
disconnect the client, thinking it had timed out, thus causing a clone
to abort.
This patch enables the changelog to compute the set of changed files as
new revisions are added. By doing so, we:
* avoid a potentially heavy computation between changelog and manifest
processing by spreading the computation across all changelog additions
* avoid extra reads from the changelog by operating on the data as it is
added
The downside of this is that the add revision callback does result in
extra I/O. Before, we would perform a flush (and subsequent read to
construct the full revision) when new delta chains were created. For
changelogs, this is typically every 2-4 revisions. Using the callback
guarantees there will be a flush after every added revision *and* an
open + read of the changelog to obtain the full revision in order to
read the added files. So, this increases the frequency of these
operations by the average chain length. In the future, the revlog
should be smart enough to know how to read revisions that haven't been
flushed yet, thus eliminating this extra I/O.
On my MBP, the total CPU times for an `hg unbundle` with a local
mozilla-central gzip bundle containing 251,934 changesets and 211,065
files did not have a statistically significant change with this patch,
holding steady around 360s. So, the increased revlog flushing did not
have an effect.
With this patch, there is no longer a visible pause between applying
changeset and manifest data. Before, it sure felt like Mercurial was
lethargic making this transition. Now, the transition is nearly
instantaneous, giving the impression that Mercurial is faster. Of course,
eliminating this pause means that the potential for network disconnect due
to channel inactivity during the changelog walk is eliminated as well.
And that is the impetus behind this change.
The computation of roots was buggy, any ancestor of a bundled merge which was
also a descendant of the parents of a bundled revision were included as part of
the bundle. We fix it and add a test for strip (which revealed the problem).
Check the test for a practical usecase.
Python 2.6 introduced the "except type as instance" syntax, replacing
the "except type, instance" syntax that came before. Python 3 dropped
support for the latter syntax. Since we no longer support Python 2.4 or
2.5, we have no need to continue supporting the "except type, instance".
This patch mass rewrites the exception syntax to be Python 2.6+ and
Python 3 compatible.
This patch was produced by running `2to3 -f except -w -n .`.
This eliminates the following test failure on Windows, as well as a similar one
in evolve's test-wireproto.t. See the previous patch for details on the
problem.
--- e:/Projects/hg/tests/test-init.t
+++ e:/Projects/hg/tests/test-init.t.err
@@ -216,10 +216,10 @@
* test 0:08b9e9f63b32
$ hg clone -e "python \"$TESTDIR/dummyssh\"" local ssh://user@dummy/remote-bookmarks
searching for changes
+ exporting bookmark test
remote: adding changesets
remote: adding manifests
remote: adding file changes
remote: added 1 changesets with 1 changes to 1 files
- exporting bookmark test
$ hg -R remote-bookmarks bookmarks
test 0:08b9e9f63b32
It is finally time to freeze the bundle2 format! To do so we:
- rename HG2Y to HG20,
- drop "b2x:" prefix from all part names,
- rename capability to "bundle2-exp" to "bundle2"
- rename the hook flag from 'bundle2-exp' to 'bundle2'
