Avoid commit-graph lock contention #2198
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The close_commit_graph() method took a repository struct, but then only uses the raw_object_store within. Change the function prototype to make the method more flexible. Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
The close_all_packs() method is used to close all read handles to pack-files and the multi-pack-index before running 'git gc --auto'. This is particularly important on the Windows platform, where read handles block any writes to those files. Replacing one of these files with a rename() will fail in this situation. The commit-graph also performs a rename, so is susceptable to this problem. We are careful to close the commit-graph before writing, but that doesn't work when a 'git fetch' (or similar) process runs 'git gc --auto' which may write a commit-graph. Here, close the commit-graph as part of close_all_packs(). Reported-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
The close_all_packs() method is now responsible for more than just pack-files. It also closes the commit-graph and the multi-pack-index. Rename the function to be more descriptive of its larger role. The name also fits because the input parameter is a raw_object_store. Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
This topic branch is a backport of gitgitgadget#208, which avoids a lock contention in `git gc --auto` where the `git gc` process holds a read lock to the `commit-graph` file (if `core.commitgraph=true`) and the spawned `git commit-graph write` (if `gc.writecommitgraph=true`) tries to overwrite it. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
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We [now avoid problems updating the commit graph](git-for-windows/git#2198) when `gc.writeCommitGraph=true`. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
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Avoid commit-graph lock contention
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This PR is a backport of gitgitgadget#208, which avoids a lock contention in
git gc --autowhere thegit gcprocess holds a read lock to thecommit-graphfile (ifcore.commitgraph=true) and the spawnedgit commit-graph write(ifgc.writecommitgraph=true) tries to overwrite it.cc @derrickstolee