summaryrefslogtreecommitdiff
path: root/t/t5324-split-commit-graph.sh
Commit message (Collapse)AuthorAgeFilesLines
* commit-graph: add --[no-]progress to write and verifyGarima Singh2019-09-181-1/+1
| | | | | | | | | | Add --[no-]progress to git commit-graph write and verify. The progress feature was introduced in 7b0f229 ("commit-graph write: add progress output", 2018-09-17) but the ability to opt-out was overlooked. Signed-off-by: Garima Singh <garima.singh@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* Merge branch 'ds/feature-macros'Junio C Hamano2019-09-091-0/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | A mechanism to affect the default setting for a (related) group of configuration variables is introduced. * ds/feature-macros: repo-settings: create feature.experimental setting repo-settings: create feature.manyFiles setting repo-settings: parse core.untrackedCache commit-graph: turn on commit-graph by default t6501: use 'git gc' in quiet mode repo-settings: consolidate some config settings
| * commit-graph: turn on commit-graph by defaultDerrick Stolee2019-08-131-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The commit-graph feature has seen a lot of activity in the past year or so since it was introduced. The feature is a critical performance enhancement for medium- to large-sized repos, and does not significantly hurt small repos. Change the defaults for core.commitGraph and gc.writeCommitGraph to true so users benefit from this feature by default. There are several places in the test suite where the environment variable GIT_TEST_COMMIT_GRAPH is disabled to avoid reading a commit-graph, if it exists. The config option overrides the environment, so swap these. Some GIT_TEST_COMMIT_GRAPH assignments remain, and those are to avoid writing a commit-graph when a new commit is created. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | commit-graph: fix bug around octopus mergesDerrick Stolee2019-08-051-1/+3
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In 1771be90 "commit-graph: merge commit-graph chains" (2019-06-18), the method sort_and_scan_merged_commits() was added to merge the commit lists of two commit-graph files in the incremental format. Unfortunately, there was an off-by-one error in that method around incrementing num_extra_edges, which leads to an incorrect offset for the base graph chunk. When we store an octopus merge in the commit-graph file, we store the first parent in the normal place, but use the second parent position to point into the "extra edges" chunk where the remaining parents exist. This means we should be adding "num_parents - 1" edges to this list, not "num_parents - 2". That is the basic error. The reason this was not caught in the test suite is more subtle. In 5324-split-commit-graph.sh, we test creating an octopus merge and adding it to the tip of a commit-graph chain, then verify the result. This _should_ have caught the problem, except that when we load the commit-graph files we were overly careful to not fail when the commit-graph chain does not match. This care was on purpose to avoid race conditions as one process reads the chain and another process modifies it. In such a case, the reading process outputs the following message to stderr: warning: commit-graph chain does not match These warnings are output in the test suite, but ignored. By checking the stderr of `git commit-graph verify` to include the expected progress output, it will now catch this error. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* commit-graph: test verify across alternatesDerrick Stolee2019-06-191-0/+19
| | | | | | | | | | | | | The 'git commit-graph verify' subcommand loads a commit-graph from a given object directory instead of using the standard method prepare_commit_graph(). During development of load_commit_graph_chain(), a version did not include prepare_alt_odb() as it was previously run by prepare_commit_graph() in most cases. Add a test that prevents that mistake from happening again. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* commit-graph: normalize commit-graph filenamesDerrick Stolee2019-06-191-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | When writing commit-graph files, we append path data to an object directory, which may be specified by the user via the '--object-dir' option. If the user supplies a trailing slash, or some other alternative path format, the resulting path may be usable for writing to the correct location. However, when expiring graph files from the <obj-dir>/info/commit-graphs directory during a write, we need to compare paths with exact string matches. Normalize the commit-graph filenames to avoid ambiguity. This creates extra allocations, but this is a constant multiple of the number of commit-graph files, which should be a number in the single digits. Further normalize the object directory in the context. Due to a comparison between g->obj_dir and ctx->obj_dir in split_graph_merge_strategy(), a trailing slash would prevent any merging of layers within the same object directory. The check is there to ensure we do not merge across alternates. Update the tests to include a case with this trailing slash problem. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* commit-graph: test --split across alternate without --splitDerrick Stolee2019-06-191-0/+15
| | | | | | | | | | | | | | | | | | | | | We allow sharing commit-graph files across alternates. When we are writing a split commit-graph, we allow adding tip graph files that are not in the alternate, but include commits from our local repo. However, if our alternate is not using the split commit-graph format, its file is at .git/objects/info/commit-graph and we are trying to write files in .git/objects/info/commit-graphs/graph-{hash}.graph. We already have logic to ensure we do not merge across alternate boundaries, but we also cannot have a commit-graph chain to our alternate if uses the old filename structure. Create a test that verifies we create a new split commit-graph with only one level and we do not modify the existing commit-graph in the alternate. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* commit-graph: test octopus merges with --splitDerrick Stolee2019-06-191-0/+11
| | | | | | | | | | | Octopus merges require an extra chunk of data in the commit-graph file format. Create a test that ensures the new --split option continues to work with an octopus merge. Specifically, ensure that the octopus merge has parents across layers to truly check that our graph position logic holds up correctly. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* commit-graph: clean up chains after flattened writeDerrick Stolee2019-06-191-0/+12
| | | | | | | | | | | | If we write a commit-graph file without the split option, then we write to $OBJDIR/info/commit-graph and start to ignore the chains in $OBJDIR/info/commit-graphs/. Unlink the commit-graph-chain file and expire the graph-{hash}.graph files in $OBJDIR/info/commit-graphs/ during every write. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* commit-graph: verify chains with --shallow modeDerrick Stolee2019-06-191-0/+62
| | | | | | | | | | | | | | | If we wrote a commit-graph chain, we only modified the tip file in the chain. It is valuable to verify what we wrote, but not waste time checking files we did not write. Add a '--shallow' option to the 'git commit-graph verify' subcommand and check that it does not read the base graph in a two-file chain. Making the verify subcommand read from a chain of commit-graphs takes some rearranging of the builtin code. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* commit-graph: create options for split filesDerrick Stolee2019-06-191-0/+47
| | | | | | | | | | | | The split commit-graph feature is now fully implemented, but needs some more run-time configurability. Allow direct callers to 'git commit-graph write --split' to specify the values used in the merge strategy and the expire time. Update the documentation to specify these values. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* commit-graph: expire commit-graph filesDerrick Stolee2019-06-191-1/+1
| | | | | | | | | | | | | | | | | As we merge commit-graph files in a commit-graph chain, we should clean up the files that are no longer used. This change introduces an 'expiry_window' value to the context, which is always zero (for now). We then check the modified time of each graph-{hash}.graph file in the $OBJDIR/info/commit-graphs folder and unlink the files that are older than the expiry_window. Since this is always zero, this immediately clears all unused graph files. We will update the value to match a config setting in a future change. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* commit-graph: allow cross-alternate chainsDerrick Stolee2019-06-191-0/+37
| | | | | | | | | | | | | | | | | | | | | | | In an environment like a fork network, it is helpful to have a commit-graph chain that spans both the base repo and the fork repo. The fork is usually a small set of data on top of the large repo, but sometimes the fork is much larger. For example, git-for-windows/git has almost double the number of commits as git/git because it rebases its commits on every major version update. To allow cross-alternate commit-graph chains, we need a few pieces: 1. When looking for a graph-{hash}.graph file, check all alternates. 2. When merging commit-graph chains, do not merge across alternates. 3. When writing a new commit-graph chain based on a commit-graph file in another object directory, do not allow success if the base file has of the name "commit-graph" instead of "commit-graphs/graph-{hash}.graph". Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* commit-graph: merge commit-graph chainsDerrick Stolee2019-06-191-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When searching for a commit in a commit-graph chain of G graphs with N commits, the search takes O(G log N) time. If we always add a new tip graph with every write, the linear G term will start to dominate and slow the lookup process. To keep lookups fast, but also keep most incremental writes fast, create a strategy for merging levels of the commit-graph chain. The strategy is detailed in the commit-graph design document, but is summarized by these two conditions: 1. If the number of commits we are adding is more than half the number of commits in the graph below, then merge with that graph. 2. If we are writing more than 64,000 commits into a single graph, then merge with all lower graphs. The numeric values in the conditions above are currently constant, but can become config options in a future update. As we merge levels of the commit-graph chain, check that the commits still exist in the repository. A garbage-collection operation may have removed those commits from the object store and we do not want to persist them in the commit-graph chain. This is a non-issue if the 'git gc' process wrote a new, single-level commit-graph file. After we merge levels, the old graph-{hash}.graph files are no longer referenced by the commit-graph-chain file. We will expire these files in a future change. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* commit-graph: add --split option to builtinDerrick Stolee2019-06-191-0/+122
Add a new "--split" option to the 'git commit-graph write' subcommand. This option allows the optional behavior of writing a commit-graph chain. The current behavior will add a tip commit-graph containing any commits that are not in the existing commit-graph or commit-graph chain. Later changes will allow merging the chain and expiring out-dated files. Add a new test script (t5324-split-commit-graph.sh) that demonstrates this behavior. Helped-by: Johannes Schindelin <Johannes.Schindelin@gmx.de> Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>