path: root/connected.h
AgeCommit message (Collapse)Author
2020-03-29connected: always use partial clone optimizationJonathan Tan
With 50033772d5 ("connected: verify promisor-ness of partial clone", 2020-01-30), the fast path (checking promisor packs) in check_connected() now passes a subset of the slow path (rev-list) - if all objects to be checked are found in promisor packs, both the fast path and the slow path will pass; otherwise, the fast path will definitely not pass. This means that we can always attempt the fast path whenever we need to do the slow path. The fast path is currently guarded by a flag; therefore, remove that flag. Also, make the fast path fallback to the slow path - if the fast path fails, the failing OID and all remaining OIDs will be passed to rev-list. The main user-visible benefit is the performance of fetch from a partial clone - specifically, the speedup of the connectivity check done before the fetch. In particular, a no-op fetch into a partial clone on my computer was sped up from 7 seconds to 0.01 seconds. This is a complement to the work in 2df1aa239c ("fetch: forgo full connectivity check if --filter", 2020-01-30), which is the child of the aforementioned 50033772d5. In that commit, the connectivity check *after* the fetch was sped up. The addition of the fast path might cause performance reductions in these cases: - If a partial clone or a fetch into a partial clone fails, Git will fruitlessly run rev-list (it is expected that everything fetched would go into promisor packs, so if that didn't happen, it is most likely that rev-list will fail too). - Any connectivity checks done by receive-pack, in the (in my opinion, unlikely) event that a partial clone serves receive-pack. I think that these cases are rare enough, and the performance reduction in this case minor enough (additional object DB access), that the benefit of avoiding a flag outweighs these. Signed-off-by: Jonathan Tan <> Reviewed-by: Josh Steadmon <> Signed-off-by: Junio C Hamano <>
2020-01-30connected: verify promisor-ness of partial cloneJonathan Tan
Commit dfa33a298d ("clone: do faster object check for partial clones", 2019-04-21) optimized the connectivity check done when cloning with --filter to check only the existence of objects directly pointed to by refs. But this is not sufficient: they also need to be promisor objects. Make this check more robust by instead checking that these objects are promisor objects, that is, they appear in a promisor pack. Signed-off-by: Jonathan Tan <> Reviewed-by: Jonathan Nieder <> Signed-off-by: Junio C Hamano <>
2019-04-21clone: do faster object check for partial clonesJosh Steadmon
For partial clones, doing a full connectivity check is wasteful; we skip promisor objects (which, for a partial clone, is all known objects), and enumerating them all to exclude them from the connectivity check can take a significant amount of time on large repos. At most, we want to make sure that we get the objects referred to by any wanted refs. For partial clones, just check that these objects were transferred. Signed-off-by: Josh Steadmon <> Signed-off-by: Junio C Hamano <>
2018-09-21connected: document connectivity in partial clonesJonathan Tan
In acb0c57260 ("fetch: support filters", 2017-12-08), check_connected() was extended to allow objects to either be promised to be available (if the repository is a partial clone) or to be present; previously, this function required the latter. However, this change was not reflected in the documentation of that function. Update the documentation accordingly. Signed-off-by: Jonathan Tan <> Signed-off-by: Junio C Hamano <>
2018-08-15Add missing includes and forward declarationsElijah Newren
I looped over the toplevel header files, creating a temporary two-line C program for each consisting of #include "git-compat-util.h" #include $HEADER This patch is the result of manually fixing errors in compiling those tiny programs. Signed-off-by: Elijah Newren <> Signed-off-by: Junio C Hamano <>
2018-07-03fetch-pack: write shallow, then check connectivityJonathan Tan
When fetching, connectivity is checked after the shallow file is updated. There are 2 issues with this: (1) the connectivity check is only performed up to ancestors of existing refs (which is not thorough enough if we were deepening an existing ref in the first place), and (2) there is no rollback of the shallow file if the connectivity check fails. To solve (1), update the connectivity check to check the ancestry chain completely in the case of a deepening fetch by refraining from passing "--not --all" when invoking rev-list in connected.c. To solve (2), have fetch_pack() perform its own connectivity check before updating the shallow file. To support existing use cases in which "git fetch-pack" is used to download objects without much regard as to the connectivity of the resulting objects with respect to the existing repository, the connectivity check is only done if necessary (that is, the fetch is not a clone, and the fetch involves shallow/deepen functionality). "git fetch" still performs its own connectivity check, preserving correctness but sometimes performing redundant work. This redundancy is mitigated by the fact that fetch_pack() reports if it has performed a connectivity check itself, and if the transport supports connect or stateless-connect, it will bubble up that report so that "git fetch" knows not to perform the connectivity check in such a case. This was noticed when a user tried to deepen an existing repository by fetching with --no-shallow from a server that did not send all necessary objects - the connectivity check as run by "git fetch" succeeded, but a subsequent "git fsck" failed. Signed-off-by: Jonathan Tan <> Signed-off-by: Junio C Hamano <>
2017-10-16Convert check_connected to use struct object_idbrian m. carlson
Convert check_connected and the callbacks it takes to use struct object_id. Signed-off-by: brian m. carlson <> Signed-off-by: Junio C Hamano <>
2016-10-10check_connected: accept an env argumentJeff King
This lets callers influence the environment seen by rev-list, which will be useful when we start providing quarantined objects. Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
2016-07-20check_connected: add progress flagJeff King
Connectivity checks have to traverse the entire object graph in the worst case (e.g., a full clone or a full push). For large repositories like linux.git, this can take 30-60 seconds, during which time git may produce little or no output. Let's add the option of showing progress, which is taken care of by rev-list. Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
2016-07-20check_connected: relay errors to alternate descriptorJeff King
Unless the "quiet" flag is given, check_connected sends any errors to the stderr of the caller (because the child rev-list inherits that descriptor). However, server-side callers may want to send these over a sideband channel instead. Let's make that possible. Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
2016-07-20check_everything_connected: use a struct with named optionsJeff King
The number of variants of check_everything_connected has grown over the years, so that the "real" function takes several possibly-zero, possibly-NULL arguments. We hid the complexity behind some wrapper functions, but this doesn't scale well when we want to add new options. If we add more wrapper variants to handle the new options, then we can get a combinatorial explosion when those options might be used together (right now nobody wants to use both "shallow" and "transport" together, so we get by with just a few wrappers). If instead we add new parameters to each function, each of which can have a default value, then callers who want the defaults end up with confusing invocations like: check_everything_connected(fn, 0, data, -1, 0, NULL); where it is unclear which parameter is which (and every caller needs updated when we add new options). Instead, let's add a struct to hold all of the optional parameters. This is a little more verbose for the callers (who have to declare the struct and fill it in), but it makes their code much easier to follow, because every option is named as it is set (and unused options do not have to be mentioned at all). Note that we could also stick the iteration function and its callback data into the option struct, too. But since those are required for each call, by avoiding doing so, we can let very simple callers just pass "NULL" for the options and not worry about the struct at all. While we're touching each site, let's also rename the function to check_connected(). The existing name was quite long, and not all of the wrappers even used the full name. Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
2013-12-11connected.c: add new variant that runs with --shallow-fileNguyễn Thái Ngọc Duy
Signed-off-by: Nguyễn Thái Ngọc Duy <> Signed-off-by: Junio C Hamano <>
2013-05-28clone: open a shortcut for connectivity checkNguyễn Thái Ngọc Duy
In order to make sure the cloned repository is good, we run "rev-list --objects --not --all $new_refs" on the repository. This is expensive on large repositories. This patch attempts to mitigate the impact in this special case. In the "good" clone case, we only have one pack. If all of the following are met, we can be sure that all objects reachable from the new refs exist, which is the intention of running "rev-list ...": - all refs point to an object in the pack - there are no dangling pointers in any object in the pack - no objects in the pack point to objects outside the pack The second and third checks can be done with the help of index-pack as a slight variation of --strict check (which introduces a new condition for the shortcut: pack transfer must be used and the number of objects large enough to call index-pack). The first is checked in check_everything_connected after we get an "ok" from index-pack. "index-pack + new checks" is still faster than the current "index-pack + rev-list", which is the whole point of this patch. If any of the conditions fail, we fall back to the good old but expensive "rev-list ..". In that case it's even more expensive because we have to pay for the new checks in index-pack. But that should only happen when the other side is either buggy or malicious. Cloning linux-2.6 over file:// before after real 3m25.693s 2m53.050s user 5m2.037s 4m42.396s sys 0m13.750s 0m16.574s A more realistic test with ssh:// over wireless before after real 11m26.629s 10m4.213s user 5m43.196s 5m19.444s sys 0m35.812s 0m37.630s This shortcut is not applied to shallow clones, partly because shallow clones should have no more objects than a usual fetch and the cost of rev-list is acceptable, partly to avoid dealing with corner cases when grafting is involved. This shortcut does not apply to unpack-objects code path either because the number of objects must be small in order to trigger that code path. Signed-off-by: Nguyễn Thái Ngọc Duy <> Signed-off-by: Junio C Hamano <>
2011-09-09check_everything_connected(): libifyJunio C Hamano
Extract the helper function and the type definition of the iterator function it uses out of builtin/fetch.c into a separate source and a header file. Signed-off-by: Junio C Hamano <>