Mercurial > hg
view Makefile @ 23785:cb99bacb9b4e
branchcache: introduce revbranchcache for caching of revision branch names
It is expensive to retrieve the branch name of a revision. Very expensive when
creating a changectx and calling .branch() every time - slightly less when
using changelog.branchinfo().
Now, to speed things up, provide a way to cache the results on disk in an
efficient format. Each branchname is assigned a number, and for each revision
we store the number of the corresponding branch name. The branch names are
stored in a dedicated file which is strictly append only.
Branch names are usually reused across several revisions, and the total list of
branch names will thus be so small that it is feasible to read the whole set of
names before using the cache. It will however do that it might be more
efficient to use the changelog for retrieving the branch info for a single
revision.
The revision entries are stored in another file. This file is usually append
only, but if the repository has been modified, the file will be truncated and
the relevant parts rewritten on demand.
The entries for each revision are 8 bytes each, and the whole revision file
will thus be 1/8 of 00changelog.i.
Each revision entry contains the first 4 bytes of the corresponding node hash.
This is used as a check sum that always is verified before the entry is used.
That check is relatively expensive but it makes sure history modification is
detected and handled correctly. It will also detect and handle most revision
file corruptions.
This is just a cache. A new format can always be introduced if other
requirements or ideas make that seem like a good idea. Rebuilding the cache is
not really more expensive than it was to run for example 'hg log -b branchname'
before this cache was introduced.
This new method is still unused but promise to make some operations several
times faster once it actually is used.
Abandoning Python 2.4 would make it possible to implement this more efficiently
by using struct classes and pack_into. The Python code could probably also be
micro optimized or it could be implemented very efficiently in C where it would
be easy to control the data access.
author | Mads Kiilerich <madski@unity3d.com> |
---|---|
date | Thu, 08 Jan 2015 00:01:03 +0100 |
parents | a5d6a609752b |
children | 272b1cc3e83e |
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# If you want to change PREFIX, do not just edit it below. The changed # value wont get passed on to recursive make calls. You should instead # override the variable on the command like: # # % make PREFIX=/opt/ install PREFIX=/usr/local export PREFIX PYTHON=python PURE= PYFILES:=$(shell find mercurial hgext doc -name '*.py') DOCFILES=mercurial/help/*.txt export LANGUAGE=C export LC_ALL=C # Set this to e.g. "mingw32" to use a non-default compiler. COMPILER= help: @echo 'Commonly used make targets:' @echo ' all - build program and documentation' @echo ' install - install program and man pages to $$PREFIX ($(PREFIX))' @echo ' install-home - install with setup.py install --home=$$HOME ($(HOME))' @echo ' local - build for inplace usage' @echo ' tests - run all tests in the automatic test suite' @echo ' test-foo - run only specified tests (e.g. test-merge1.t)' @echo ' dist - run all tests and create a source tarball in dist/' @echo ' clean - remove files created by other targets' @echo ' (except installed files or dist source tarball)' @echo ' update-pot - update i18n/hg.pot' @echo @echo 'Example for a system-wide installation under /usr/local:' @echo ' make all && su -c "make install" && hg version' @echo @echo 'Example for a local installation (usable in this directory):' @echo ' make local && ./hg version' all: build doc local: $(PYTHON) setup.py $(PURE) \ build_py -c -d . \ build_ext $(COMPILER:%=-c %) -i \ build_hgexe $(COMPILER:%=-c %) -i \ build_mo env HGRCPATH= $(PYTHON) hg version build: $(PYTHON) setup.py $(PURE) build $(COMPILER:%=-c %) doc: $(MAKE) -C doc clean: -$(PYTHON) setup.py clean --all # ignore errors from this command find contrib doc hgext i18n mercurial tests \ \( -name '*.py[cdo]' -o -name '*.so' \) -exec rm -f '{}' ';' rm -f $(addprefix mercurial/,$(notdir $(wildcard mercurial/pure/[a-z]*.py))) rm -f MANIFEST MANIFEST.in hgext/__index__.py tests/*.err if test -d .hg; then rm -f mercurial/__version__.py; fi rm -rf build mercurial/locale $(MAKE) -C doc clean install: install-bin install-doc install-bin: build $(PYTHON) setup.py $(PURE) install --root="$(DESTDIR)/" --prefix="$(PREFIX)" --force install-doc: doc cd doc && $(MAKE) $(MFLAGS) install install-home: install-home-bin install-home-doc install-home-bin: build $(PYTHON) setup.py $(PURE) install --home="$(HOME)" --prefix="" --force install-home-doc: doc cd doc && $(MAKE) $(MFLAGS) PREFIX="$(HOME)" install MANIFEST-doc: $(MAKE) -C doc MANIFEST MANIFEST.in: MANIFEST-doc hg manifest | sed -e 's/^/include /' > MANIFEST.in echo include mercurial/__version__.py >> MANIFEST.in sed -e 's/^/include /' < doc/MANIFEST >> MANIFEST.in dist: tests dist-notests dist-notests: doc MANIFEST.in TAR_OPTIONS="--owner=root --group=root --mode=u+w,go-w,a+rX-s" $(PYTHON) setup.py -q sdist check: tests tests: cd tests && $(PYTHON) run-tests.py $(TESTFLAGS) test-%: cd tests && $(PYTHON) run-tests.py $(TESTFLAGS) $@ check-code: hg manifest | xargs python contrib/check-code.py update-pot: i18n/hg.pot i18n/hg.pot: $(PYFILES) $(DOCFILES) i18n/posplit i18n/hggettext $(PYTHON) i18n/hggettext mercurial/commands.py \ hgext/*.py hgext/*/__init__.py \ mercurial/fileset.py mercurial/revset.py \ mercurial/templatefilters.py mercurial/templatekw.py \ mercurial/filemerge.py \ $(DOCFILES) > i18n/hg.pot.tmp # All strings marked for translation in Mercurial contain # ASCII characters only. But some files contain string # literals like this '\037\213'. xgettext thinks it has to # parse them even though they are not marked for translation. # Extracting with an explicit encoding of ISO-8859-1 will make # xgettext "parse" and ignore them. echo $(PYFILES) | xargs \ xgettext --package-name "Mercurial" \ --msgid-bugs-address "<mercurial-devel@selenic.com>" \ --copyright-holder "Matt Mackall <mpm@selenic.com> and others" \ --from-code ISO-8859-1 --join --sort-by-file --add-comments=i18n: \ -d hg -p i18n -o hg.pot.tmp $(PYTHON) i18n/posplit i18n/hg.pot.tmp # The target file is not created before the last step. So it never is in # an intermediate state. mv -f i18n/hg.pot.tmp i18n/hg.pot %.po: i18n/hg.pot # work on a temporary copy for never having a half completed target cp $@ $@.tmp msgmerge --no-location --update $@.tmp $^ mv -f $@.tmp $@ # Packaging targets osx: @which bdist_mpkg >/dev/null || \ (echo "Missing bdist_mpkg (easy_install bdist_mpkg)"; false) rm -rf dist/mercurial-*.mpkg bdist_mpkg setup.py mkdir -p packages/osx N=`cd dist && echo mercurial-*.mpkg | sed 's,\.mpkg$$,,'` && hdiutil create -srcfolder dist/$$N.mpkg/ -scrub -volname "$$N" -ov packages/osx/$$N.dmg rm -rf dist/mercurial-*.mpkg fedora20: mkdir -p packages/fedora20 contrib/buildrpm cp rpmbuild/RPMS/*/* packages/fedora20 cp rpmbuild/SRPMS/* packages/fedora20 rm -rf rpmbuild docker-fedora20: mkdir -p packages/fedora20 contrib/dockerrpm fedora20 centos5: mkdir -p packages/centos5 contrib/buildrpm --withpython cp rpmbuild/RPMS/*/* packages/centos5 cp rpmbuild/SRPMS/* packages/centos5 docker-centos5: mkdir -p packages/centos5 contrib/dockerrpm centos5 --withpython centos6: mkdir -p packages/centos6 contrib/buildrpm cp rpmbuild/RPMS/*/* packages/centos6 cp rpmbuild/SRPMS/* packages/centos6 docker-centos6: mkdir -p packages/centos6 contrib/dockerrpm centos6 centos7: mkdir -p packages/centos7 contrib/buildrpm cp rpmbuild/RPMS/*/* packages/centos7 cp rpmbuild/SRPMS/* packages/centos7 docker-centos7: mkdir -p packages/centos7 contrib/dockerrpm centos7 .PHONY: help all local build doc clean install install-bin install-doc \ install-home install-home-bin install-home-doc \ dist dist-notests check tests check-code update-pot \ osx fedora20 docker-fedora20 \ centos5 docker-centos5 centos6 docker-centos6 centos7 docker-centos7