git/builtin/fetch.c, branch v2.34.2

Merge branch 'js/run-command-close-packs'

2021-09-20T22:20:45Z

The run-command API has been updated so that the callers can easily ask the file descriptors open for packfiles to be closed immediately before spawning commands that may trigger auto-gc. * js/run-command-close-packs: Close object store closer to spawning child processes run_auto_maintenance(): implicitly close the object store run-command: offer to close the object store before running run-command: prettify the `RUN_COMMAND_*` flags pull: release packs before fetching commit-graph: when closing the graph, also release the slab

Merge branch 'ps/fetch-optim'

2021-09-20T22:20:39Z

Optimize code that handles large number of refs in the "git fetch" code path. * ps/fetch-optim: fetch: avoid second connectivity check if we already have all objects fetch: merge fetching and consuming refs fetch: refactor fetch refs to be more extendable fetch-pack: optimize loading of refs via commit graph connected: refactor iterator to return next object ID directly fetch: avoid unpacking headers in object existence check fetch: speed up lookup of want refs via commit-graph

Merge branch 'ab/retire-advice-config'

2021-09-10T18:46:29Z

Code clean up to migrate callers from older advice_config[] based API to newer advice_if_enabled() and advice_enabled() API. * ab/retire-advice-config: advice: move advice.graftFileDeprecated squashing to commit.[ch] advice: remove use of global advice_add_embedded_repo advice: remove read uses of most global `advice_` variables advice: add enum variants for missing advice variables

Merge branch 'ps/fetch-omit-formatting-under-quiet'

2021-09-10T18:46:20Z

"git fetch --quiet" optimization to avoid useless computation of info that will never be displayed. * ps/fetch-omit-formatting-under-quiet: fetch: skip formatting updated refs with `--quiet`

run_auto_maintenance(): implicitly close the object store

2021-09-09T19:56:11Z

Before spawning the auto maintenance, we need to make sure that we release all open file handles to all the `.pack` files (and MIDX files and commit-graph files and...) so that the maintenance process has the freedom to delete those files. So far, we did this manually every time before calling `run_auto_maintenance()`. With the new `close_object_store` flag, we can do that implicitly in that function, which is more robust because future callers won't be able to forget to close the object store. Note: this changes behavior slightly, as we previously _always_ closed the object store, but now we only close the object store when actually running the auto maintenance. In practice, this should not matter (if anything, it might speed up operations where auto maintenance is disabled). Suggested-by: Junio C Hamano Signed-off-by: Johannes Schindelin Signed-off-by: Junio C Hamano

fetch: avoid second connectivity check if we already have all objects

2021-09-01T19:43:56Z

When fetching refs, we are doing two connectivity checks: - The first one is done such that we can skip fetching refs in the case where we already have all objects referenced by the updated set of refs. - The second one verifies that we have all objects after we have fetched objects. We always execute both connectivity checks, but this is wasteful in case the first connectivity check already notices that we have all objects locally available. Skip the second connectivity check in case we already had all objects available. This gives us a nice speedup when doing a mirror-fetch in a repository with about 2.3M refs where the fetching repo already has all objects: Benchmark #1: HEAD~: git-fetch Time (mean ± σ): 30.025 s ± 0.081 s [User: 27.070 s, System: 4.933 s] Range (min … max): 29.900 s … 30.111 s 5 runs Benchmark #2: HEAD: git-fetch Time (mean ± σ): 25.574 s ± 0.177 s [User: 22.855 s, System: 4.683 s] Range (min … max): 25.399 s … 25.765 s 5 runs Summary 'HEAD: git-fetch' ran 1.17 ± 0.01 times faster than 'HEAD~: git-fetch' Signed-off-by: Patrick Steinhardt Signed-off-by: Junio C Hamano

fetch: merge fetching and consuming refs

2021-09-01T19:43:56Z

The functions `fetch_refs()` and `consume_refs()` must always be called together such that we first obtain all missing objects and then update our local refs to match the remote refs. In a subsequent patch, we'll further require that `fetch_refs()` must always be called before `consume_refs()` such that it can correctly assert that we have all objects after the fetch given that we're about to move the connectivity check. Make this requirement explicit by merging both functions into a single `fetch_and_consume_refs()` function. Signed-off-by: Patrick Steinhardt Signed-off-by: Junio C Hamano

fetch: refactor fetch refs to be more extendable

2021-09-01T19:43:56Z

Refactor `fetch_refs()` code to make it more extendable by explicitly handling error cases. The refactored code should behave the same. Signed-off-by: Patrick Steinhardt Signed-off-by: Junio C Hamano

connected: refactor iterator to return next object ID directly

2021-09-01T19:43:56Z

The object ID iterator used by the connectivity checks returns the next object ID via an out-parameter and then uses a return code to indicate whether an item was found. This is a bit roundabout: instead of a separate error code, we can just return the next object ID directly and use `NULL` pointers as indicator that the iterator got no items left. Furthermore, this avoids a copy of the object ID. Refactor the iterator and all its implementations to return object IDs directly. This brings a tiny performance improvement when doing a mirror-fetch of a repository with about 2.3M refs: Benchmark #1: 328dc58b49919c43897240f2eabfa30be2ce32a4~: git-fetch Time (mean ± σ): 30.110 s ± 0.148 s [User: 27.161 s, System: 5.075 s] Range (min … max): 29.934 s … 30.406 s 10 runs Benchmark #2: 328dc58b49919c43897240f2eabfa30be2ce32a4: git-fetch Time (mean ± σ): 29.899 s ± 0.109 s [User: 26.916 s, System: 5.104 s] Range (min … max): 29.696 s … 29.996 s 10 runs Summary '328dc58b49919c43897240f2eabfa30be2ce32a4: git-fetch' ran 1.01 ± 0.01 times faster than '328dc58b49919c43897240f2eabfa30be2ce32a4~: git-fetch' While this 1% speedup could be labelled as statistically insignificant, the speedup is consistent on my machine. Furthermore, this is an end to end test, so it is expected that the improvement in the connectivity check itself is more significant. Signed-off-by: Patrick Steinhardt Signed-off-by: Junio C Hamano

fetch: avoid unpacking headers in object existence check

2021-09-01T19:43:56Z

When updating local refs after the fetch has transferred all objects, we do an object existence test as a safety guard to avoid updating a ref to an object which we don't have. We do so via `oid_object_info()`: if it returns an error, then we know the object does not exist. One side effect of `oid_object_info()` is that it parses the object's type, and to do so it must unpack the object header. This is completely pointless: we don't care for the type, but only want to assert that the object exists. Refactor the code to use `repo_has_object_file()`, which both makes the code's intent clearer and is also faster because it does not unpack object headers. In a real-world repo with 2.3M refs, this results in a small speedup when doing a mirror-fetch: Benchmark #1: HEAD~: git-fetch Time (mean ± σ): 33.686 s ± 0.176 s [User: 30.119 s, System: 5.262 s] Range (min … max): 33.512 s … 33.944 s 5 runs Benchmark #2: HEAD: git-fetch Time (mean ± σ): 31.247 s ± 0.195 s [User: 28.135 s, System: 5.066 s] Range (min … max): 30.948 s … 31.472 s 5 runs Summary 'HEAD: git-fetch' ran 1.08 ± 0.01 times faster than 'HEAD~: git-fetch' Signed-off-by: Patrick Steinhardt Signed-off-by: Junio C Hamano