outgoing: add a simple fastpath when there is no common This further speed up case like `hg bundle --all` for larger repository. ### data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog # 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 before: 316.749699 after: 311.165461 (-1.76%, -5.58) There is further work to be done in this area like not doing any outgoing computation in the stream case for example. however the recent changes already gives use a large win for a small amount of local work. ### 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 = mercurial-public-2024-03-22-zstd-sparse-revlog pre-%ln-change: 1.263859 the-%ln-change: 0.700229 (-44.60%, -0.56) prev-changeset: 0.496050 (-60.75%, -0.77) this-changeset: 0.495243 (-60.81%, -0.77) ## data-env-vars.name = tryton-public-2024-03-22-zstd-sparse-revlog pre-%ln-change: 2.975765 the-%ln-change: 1.870798 (-37.13%, -1.10) prev-changeset: 1.461583 (-50.88%, -1.51) this-changeset: 1.469185 (-50.63%, -1.51) ## data-env-vars.name = pypy-2024-03-22-zstd-sparse-revlog pre-%ln-change: 4.540080 the-%ln-change: 3.401700 (-25.07%, -1.14) prev-changeset: 2.915810 (-35.78%, -1.62) this-changeset: 2.911643 (-35.87%, -1.63) ## data-env-vars.name = heptapod-public-2024-03-25-zstd-sparse-revlog pre-%ln-change: 10.138396 the-%ln-change: 7.750458 (-23.55%, -2.39) prev-changeset: 6.665565 (-34.25%, -3.47) this-changeset: 6.672078 (-34.19%, -3.47) ## data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog pre-%ln-change: 399.484481 the-%ln-change: 346.508952 (-13.26%, -52.98) prev-changeset: 316.749699 (-20.71%, -82.73) this-changeset: 311.165461 (-22.11%, -88.32)

Test how largefiles abort in case the disk runs full

  $ cat > criple.py <<EOF
  > import errno
  > import os
  > import shutil
  > from mercurial import util
  > #
  > # this makes the original largefiles code abort:
  > _origcopyfileobj = shutil.copyfileobj
  > def copyfileobj(fsrc, fdst, length=16 * 1024):
  >     # allow journal files (used by transaction) to be written
  >     if b'journal.' in fdst.name or b'backup.' in fdst.name:
  >         return _origcopyfileobj(fsrc, fdst, length)
  >     fdst.write(fsrc.read(4))
  >     raise IOError(errno.ENOSPC, os.strerror(errno.ENOSPC))
  > shutil.copyfileobj = copyfileobj
  > #
  > # this makes the rewritten code abort:
  > def filechunkiter(f, size=131072, limit=None):
  >     yield f.read(4)
  >     raise IOError(errno.ENOSPC, os.strerror(errno.ENOSPC))
  > util.filechunkiter = filechunkiter
  > #
  > def oslink(src, dest):
  >     raise OSError("no hardlinks, try copying instead")
  > util.oslink = oslink
  > EOF

  $ echo "[extensions]" >> $HGRCPATH
  $ echo "largefiles =" >> $HGRCPATH

  $ hg init alice
  $ cd alice
  $ echo "this is a very big file" > big
  $ hg add --large big
  $ hg commit --config extensions.criple=$TESTTMP/criple.py -m big
  abort: No space left on device
  [255]

The largefile is not created in .hg/largefiles:

  $ ls .hg/largefiles
  dirstate

The user cache is not even created:

  >>> import os; os.path.exists("$HOME/.cache/largefiles/")
  False

Make the commit with space on the device:

  $ hg commit -m big

Now make a clone with a full disk, and make sure lfutil.link function
makes copies instead of hardlinks:

  $ cd ..
  $ hg --config extensions.criple=$TESTTMP/criple.py clone --pull alice bob
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  new changesets 390cf214e9ac
  updating to branch default
  getting changed largefiles
  abort: No space left on device
  [255]

The largefile is not created in .hg/largefiles:

  $ ls bob/.hg/largefiles
  dirstate