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path: root/builtin/fetch-pack.c
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2012-10-29fetch-pack: move core code to libgit.aNguyễn Thái Ngọc Duy
fetch_pack() is used by transport.c, part of libgit.a while it stays in builtin/fetch-pack.c. Move it to fetch-pack.c so that we won't get undefined reference if a program that uses libgit.a happens to pull it in. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Jeff King <peff@peff.net>
2012-10-29fetch-pack: remove global (static) configuration variable "args"Nguyễn Thái Ngọc Duy
This helps removes the hack in fetch_pack() that copies my_args to args. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Jeff King <peff@peff.net>
2012-09-12fetch-pack: eliminate spurious error messagesMichael Haggerty
It used to be that if "--all", "--depth", and also explicit references were sought, then the explicit references were not handled correctly in filter_refs() because the "--all --depth" code took precedence over the explicit reference handling, and the explicit references were never noted as having been found. So check for explicitly sought references before proceeding to the "--all --depth" logic. This fixes two test cases in t5500. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-12cmd_fetch_pack(): simplify computation of return valueMichael Haggerty
Set the final value at initialization rather than initializing it then sometimes changing it. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-12fetch-pack: report missing refs even if no existing refs were receivedMichael Haggerty
This fixes a test in t5500. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-12cmd_fetch_pack(): return early if finish_connect() failsMichael Haggerty
This simplifies the logic without changing the behavior. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-12filter_refs(): simplify logicMichael Haggerty
Simplify flow within loop: first decide whether to keep the reference, then keep/free it. This makes it clearer that each ref has exactly two possible destinies, and removes duplication of the code for appending the reference to the linked list. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-12filter_refs(): build refs list as we goMichael Haggerty
Instead of temporarily storing matched refs to temporary array "return_refs", simply append them to newlist as we go. This changes the order of references in newlist to strictly sorted if "--all" and "--depth" and named references are all specified, but that usage is broken anyway (see the last two tests in t5500). This changes the last test in t5500 from segfaulting into just emitting a spurious error (this will be fixed in a moment). Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-12filter_refs(): delete matched refs from sought listMichael Haggerty
Remove any references that are available from the remote from the sought list (rather than overwriting their names with NUL characters, as previously). Mark matching entries by writing a non-NULL pointer to string_list_item::util during the iteration, then use filter_string_list() later to filter out the entries that have been marked. Document this aspect of fetch_pack() in a comment in the header file. (More documentation is obviously still needed.) Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-12fetch_pack(): update sought->nr to reflect number of unique entriesMichael Haggerty
fetch_pack() removes duplicates from the "sought" list, thereby shrinking the list. But previously, the caller was not informed about the shrinkage. This would cause a spurious error message to be emitted by cmd_fetch_pack() if "git fetch-pack" is called with duplicate refnames. Instead, remove duplicates using string_list_remove_duplicates(), which adjusts sought->nr to reflect the new length of the list. The last test of t5500 inexplicably *required* "git fetch-pack" to fail when fetching a list of references that contains duplicates; i.e., it insisted on the buggy behavior. So change the test to expect the correct behavior. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-12filter_refs(): do not check the same sought_pos twiceMichael Haggerty
Once a match has been found at sought_pos, the entry is zeroed and no future attempts will match that entry. So increment sought_pos to avoid checking against the zeroed-out entry during the next iteration. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-12Change fetch_pack() and friends to take string_list argumentsMichael Haggerty
Instead of juggling <nr_heads,heads> (sometimes called <nr_match,match>), pass around the list of references to be sought in a single string_list variable called "sought". Future commits will make more use of string_list functionality. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-12fetch_pack(): reindent function decl and defnMichael Haggerty
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-08-14fetch-pack: mention server version with verbose outputJeff King
Fetch-pack's verbose mode is more of a debugging mode (and in fact takes two "-v" arguments to trigger via the porcelain layer). Let's mention the server version as another possible item of interest. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-08-10fetch-pack: do not ask for unadvertised capabilitiesJunio C Hamano
In the same spirit as the previous fix, stop asking for thin-pack, no-progress and include-tag capabilities when the other end does not claim to support them. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-08-10do not send client agent unless server does firstJeff King
Commit ff5effdf taught both clients and servers of the git protocol to send an "agent" capability that just advertises their version for statistics and debugging purposes. The protocol-capabilities.txt document however indicates that the client's advertisement is actually a response, and should never include capabilities not mentioned in the server's advertisement. Adding the unconditional advertisement in the server programs was OK, then, but the clients broke the protocol. The server implementation of git-core itself does not care, but at least one does: the Google Code git server (or any server using Dulwich), will hang up with an internal error upon seeing an unknown capability. Instead, each client must record whether we saw an agent string from the server, and respond with its agent only if the server mentioned it first. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-08-03include agent identifier in capability stringJeff King
Instead of having the client advertise a particular version number in the git protocol, we have managed extensions and backwards compatibility by having clients and servers advertise capabilities that they support. This is far more robust than having each side consult a table of known versions, and provides sufficient information for the protocol interaction to complete. However, it does not allow servers to keep statistics on which client versions are being used. This information is not necessary to complete the network request (the capabilities provide enough information for that), but it may be helpful to conduct a general survey of client versions in use. We already send the client version in the user-agent header for http requests; adding it here allows us to gather similar statistics for non-http requests. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-29Merge branch 'jk/fetch-pack-remove-dups-optim'Junio C Hamano
The way "fetch-pack" that is given multiple references to fetch tried to remove duplicates was very inefficient. By Jeff King * jk/fetch-pack-remove-dups-optim: fetch-pack: sort incoming heads list earlier fetch-pack: avoid quadratic loop in filter_refs fetch-pack: sort the list of incoming refs add sorting infrastructure for list refs fetch-pack: avoid quadratic behavior in remove_duplicates fetch-pack: sort incoming heads
2012-05-29Merge branch 'mh/fetch-pack-constness'Junio C Hamano
Tighten constness of some local variables in a callchain. By Michael Haggerty * mh/fetch-pack-constness: cmd_fetch_pack(): respect constness of argv parameter cmd_fetch_pack(): combine the loop termination conditions cmd_fetch_pack(): handle non-option arguments outside of the loop cmd_fetch_pack(): declare dest to be const
2012-05-24fetch-pack: sort incoming heads list earlierJeff King
Commit 4435968 started sorting heads fed to fetch-pack so that later commits could use more optimized algorithms; commit 7db8d53 switched the remove_duplicates function to such an algorithm. Of course, the sorting is more effective if you do it _before_ the algorithm in question. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-22fetch-pack: avoid quadratic loop in filter_refsJeff King
We have a list of refs that we want to compare against the "match" array. The current code searches the match list linearly, giving quadratic behavior over the number of refs when you want to fetch all of them. Instead, we can compare the lists as we go, giving us linear behavior. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-22fetch-pack: sort the list of incoming refsJeff King
Having the list sorted means we can avoid some quadratic algorithms when comparing lists. These should typically be sorted already, but they do come from the remote, so let's be extra careful. Our ref-sorting implementation does a mergesort, so we do not have to care about performance degrading in the common case that the list is already sorted. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-22fetch-pack: avoid quadratic behavior in remove_duplicatesJeff King
We remove duplicate entries from the list of refs we are fed in fetch-pack. The original algorithm is quadratic over the number of refs, but since the list is now guaranteed to be sorted, we can do it in linear time. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-22fetch-pack: sort incoming headsJeff King
There's no reason to preserve the incoming order of the heads we're requested to fetch. By having them sorted, we can replace some of the quadratic algorithms with linear ones. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-22cmd_fetch_pack(): respect constness of argv parameterMichael Haggerty
The old code cast away the constness of the strings passed to the function in argument argv[], which could result in their being modified by filter_refs(). Fix by copying reference names from argv and putting them into our own array (similarly to how refnames passed to stdin were already handled). Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-22cmd_fetch_pack(): combine the loop termination conditionsMichael Haggerty
If an argument that does not start with '-' is found, the loop is terminated. So move that check into the for-loop condition. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-22cmd_fetch_pack(): handle non-option arguments outside of the loopMichael Haggerty
This makes it more obvious that the code is always executed unless there is an error, and that the first initialization of nr_heads is unnecessary. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-22cmd_fetch_pack(): declare dest to be constMichael Haggerty
There is no need for it to be non-const, and this avoids the need for casting away the constness of an argv element. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-04-24Merge branch 'it/fetch-pack-many-refs'Junio C Hamano
When "git fetch" encounters repositories with too many references, the command line of "fetch-pack" that is run by a helper e.g. remote-curl, may fail to hold all of them. Now such an internal invocation can feed the references through the standard input of "fetch-pack". By Ivan Todoroski * it/fetch-pack-many-refs: remote-curl: main test case for the OS command line overflow fetch-pack: test cases for the new --stdin option remote-curl: send the refs to fetch-pack on stdin fetch-pack: new --stdin option to read refs from stdin
2012-04-02fetch-pack: new --stdin option to read refs from stdinIvan Todoroski
If a remote repo has too many tags (or branches), cloning it over the smart HTTP transport can fail because remote-curl.c puts all the refs from the remote repo on the fetch-pack command line. This can make the command line longer than the global OS command line limit, causing fetch-pack to fail. This is especially a problem on Windows where the command line limit is orders of magnitude shorter than Linux. There are already real repos out there that msysGit cannot clone over smart HTTP due to this problem. Here is an easy way to trigger this problem: git init too-many-refs cd too-many-refs echo bla > bla.txt git add . git commit -m test sha=$(git rev-parse HEAD) tag=$(perl -e 'print "bla" x 30') for i in `seq 50000`; do echo $sha refs/tags/$tag-$i >> .git/packed-refs done Then share this repo over the smart HTTP protocol and try cloning it: $ git clone http://localhost/.../too-many-refs/.git Cloning into 'too-many-refs'... fatal: cannot exec 'fetch-pack': Argument list too long 50k tags is obviously an absurd number, but it is required to demonstrate the problem on Linux because it has a much more generous command line limit. On Windows the clone fails with as little as 500 tags in the above loop, which is getting uncomfortably close to the number of tags you might see in real long lived repos. This is not just theoretical, msysGit is already failing to clone our company repo due to this. It's a large repo converted from CVS, nearly 10 years of history. Four possible solutions were discussed on the Git mailing list (in no particular order): 1) Call fetch-pack multiple times with smaller batches of refs. This was dismissed as inefficient and inelegant. 2) Add option --refs-fd=$n to pass a an fd from where to read the refs. This was rejected because inheriting descriptors other than stdin/stdout/stderr through exec() is apparently problematic on Windows, plus it would require changes to the run-command API to open extra pipes. 3) Add option --refs-from=$tmpfile to pass the refs using a temp file. This was not favored because of the temp file requirement. 4) Add option --stdin to pass the refs on stdin, one per line. In the end this option was chosen as the most efficient and most desirable from scripting perspective. There was however a small complication when using stdin to pass refs to fetch-pack. The --stateless-rpc option to fetch-pack also uses stdin for communication with the remote server. If we are going to sneak refs on stdin line by line, it would have to be done very carefully in the presence of --stateless-rpc, because when reading refs line by line we might read ahead too much data into our buffer and eat some of the remote protocol data which is also coming on stdin. One way to solve this would be to refactor get_remote_heads() in fetch-pack.c to accept a residual buffer from our stdin line parsing above, but this function is used in several places so other callers would be burdened by this residual buffer interface even when most of them don't need it. In the end we settled on the following solution: If --stdin is specified without --stateless-rpc, fetch-pack would read the refs from stdin one per line, in a script friendly format. However if --stdin is specified together with --stateless-rpc, fetch-pack would read the refs from stdin in packetized format (pkt-line) with a flush packet terminating the list of refs. This way we can read the exact number of bytes that we need from stdin, and then get_remote_heads() can continue reading from the same fd without losing a single byte of remote protocol data. This way the --stdin option only loses generality and scriptability when used together with --stateless-rpc, which is not easily scriptable anyway because it also uses pkt-line when talking to the remote server. Signed-off-by: Ivan Todoroski <grnch@gmx.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-02-20Merge branch 'cb/transfer-no-progress'Junio C Hamano
* cb/transfer-no-progress: push/fetch/clone --no-progress suppresses progress output
2012-02-13push/fetch/clone --no-progress suppresses progress outputClemens Buchacher
By default, progress output is disabled if stderr is not a terminal. The --progress option can be used to force progress output anyways. Conversely, --no-progress does not force progress output. In particular, if stderr is a terminal, progress output is enabled. This is unintuitive. Change --no-progress to force output off. Signed-off-by: Clemens Buchacher <drizzd@aon.at> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-02-13everything_local(): mark alternate refs as completeMichael Haggerty
Objects in an alternate object database are already available to the local repository and therefore don't need to be fetched. So mark them as complete in everything_local(). This fixes a test in t5700. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-02-13fetch-pack.c: inline insert_alternate_refs()Michael Haggerty
The logic of the (single) caller is clearer without encapsulating this one line in a function. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-02-13fetch-pack.c: rename some parameters from "path" to "refname"Michael Haggerty
The parameters denote reference names, which are no longer 1:1 with filesystem paths. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-12-13fetch-pack: match refs exactlyJeff King
When we are determining the list of refs to fetch via fetch-pack, we have two sets of refs to compare: those on the remote side, and a "match" list of things we want to fetch. We iterate through the remote refs alphabetically, seeing if each one is wanted by the "match" list. Since def88e9 (Commit first cut at "git-fetch-pack", 2005-07-04), we have used the "path_match" function to do a suffix match, where a remote ref is considered wanted if any of the "match" elements is a suffix of the remote refname. This enables callers of fetch-pack to specify unqualified refs and have them matched up with remote refs (e.g., ask for "A" and get remote's "refs/heads/A"). However, if you provide a fully qualified ref, then there are corner cases where we provide the wrong answer. For example, given a remote with two refs: refs/foo/refs/heads/master refs/heads/master asking for "refs/heads/master" will first match "refs/foo/refs/heads/master" by the suffix rule, and we will erroneously fetch it instead of refs/heads/master. As it turns out, all callers of fetch_pack do provide fully-qualified refs for the match list. There are two ways fetch_pack can get match lists: 1. Through the transport code (i.e., via git-fetch) 2. On the command-line of git-fetch-pack In the first case, we will always be providing the names of fully-qualified refs from "struct ref" objects. We will have pre-matched those ref objects already (since we have to handle more advanced matching, like wildcard refspecs), and are just providing a list of the refs whose objects we need. In the second case, users could in theory be providing non-qualified refs on the command-line. However, the fetch-pack documentation claims that refs should be fully qualified (and has always done so since it was written in 2005). Let's change this path_match call to simply check for string equality, matching what the callers of fetch_pack are expecting. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-12-13drop "match" parameter from get_remote_headsJeff King
The get_remote_heads function reads the list of remote refs during git protocol session. It dates all the way back to def88e9 (Commit first cut at "git-fetch-pack", 2005-07-04). At that time, the idea was to come up with a list of refs we were interested in, and then filter the list as we got it from the remote side. Later, 1baaae5 (Make maximal use of the remote refs, 2005-10-28) stopped filtering at the get_remote_heads layer, letting us use the non-matching refs to find common history. As a result, all callers now simply pass an empty match list (and any future callers will want to do the same). So let's drop these now-useless parameters. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-10-10Merge branch 'mh/check-ref-format-3'Junio C Hamano
* mh/check-ref-format-3: (23 commits) add_ref(): verify that the refname is formatted correctly resolve_ref(): expand documentation resolve_ref(): also treat a too-long SHA1 as invalid resolve_ref(): emit warnings for improperly-formatted references resolve_ref(): verify that the input refname has the right format remote: avoid passing NULL to read_ref() remote: use xstrdup() instead of strdup() resolve_ref(): do not follow incorrectly-formatted symbolic refs resolve_ref(): extract a function get_packed_ref() resolve_ref(): turn buffer into a proper string as soon as possible resolve_ref(): only follow a symlink that contains a valid, normalized refname resolve_ref(): use prefixcmp() resolve_ref(): explicitly fail if a symlink is not readable Change check_refname_format() to reject unnormalized refnames Inline function refname_format_print() Make collapse_slashes() allocate memory for its result Do not allow ".lock" at the end of any refname component Refactor check_refname_format() Change check_ref_format() to take a flags argument Change bad_ref_char() to return a boolean value ...
2011-10-05Change check_ref_format() to take a flags argumentMichael Haggerty
Change check_ref_format() to take a flags argument that indicates what is acceptable in the reference name (analogous to "git check-ref-format"'s "--allow-onelevel" and "--refspec-pattern"). This is more convenient for callers and also fixes a failure in the test suite (and likely elsewhere in the code) by enabling "onelevel" and "refspec-pattern" to be allowed independently of each other. Also rename check_ref_format() to check_refname_format() to make it obvious that it deals with refnames rather than references themselves. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-10-05Merge branch 'jc/fetch-pack-fsck-objects'Junio C Hamano
* jc/fetch-pack-fsck-objects: test: fetch/receive with fsckobjects transfer.fsckobjects: unify fetch/receive.fsckobjects fetch.fsckobjects: verify downloaded objects Conflicts: Documentation/config.txt builtin/fetch-pack.c
2011-09-04transfer.fsckobjects: unify fetch/receive.fsckobjectsJunio C Hamano
This single variable can be used to set instead of setting fsckobjects variable for fetch & receive independently. Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-09-04fetch.fsckobjects: verify downloaded objectsJunio C Hamano
This corresponds to receive.fsckobjects configuration variable added (a lot) earlier in 20dc001 (receive-pack: allow using --strict mode for unpacking objects, 2008-02-25). Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-08-29Merge branch 'nd/decorate-grafts'Junio C Hamano
* nd/decorate-grafts: log: Do not decorate replacements with --no-replace-objects log: decorate "replaced" on to replaced commits log: decorate grafted commits with "grafted" Move write_shallow_commits to fetch-pack.c Add for_each_commit_graft() to iterate all grafts decoration: do not mis-decorate refs with same prefix
2011-08-18fetch-pack: check for valid commit from serverNguyễn Thái Ngọc Duy
A malicious server can return ACK with non-existent SHA-1 or not a commit. lookup_commit() in this case may return NULL. Do not let fetch-pack crash by accessing NULL address in this case. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-08-18Move write_shallow_commits to fetch-pack.cNguyễn Thái Ngọc Duy
This function produces network traffic and should be in fetch-pack. It has been in commit.c because it needs to iterate (private) graft list. It can now do so using for_each_commit_graft(). Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-05-30Merge branch 'jk/haves-from-alternate-odb'Junio C Hamano
* jk/haves-from-alternate-odb: receive-pack: eliminate duplicate .have refs bisect: refactor sha1_array into a generic sha1 list refactor refs_from_alternate_cb to allow passing extra data
2011-05-20refactor refs_from_alternate_cb to allow passing extra dataJeff King
The foreach_alt_odb function triggers a callback for each alternate object db we have, with room for a single void pointer as data. Currently, we always call refs_from_alternate_cb as the callback function, and then pass another callback (to receive each ref individually) as the void pointer. This has two problems: 1. C technically forbids stuffing a function pointer into a "void *". In practice, this probably doesn't matter on any architectures git runs on, but it never hurts to follow the letter of the law. 2. There is no room for an extra data pointer. Indeed, the alternate_ref_fn that refs_from_alternate_cb calls takes a void* for data, but we always pass it NULL. Instead, let's properly stuff our function pointer into a data struct, which also leaves room for an extra caller-supplied data pointer. And to keep things simple for existing callers, let's make a for_each_alternate_ref function that takes care of creating the extra struct. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-05-20fetch: avoid repeated commits in mark_completeJeff King
We add every local ref to a list so that we can mark them and all of their ancestors back to a certain cutoff point. However, if some refs point to the same commit, we will end up adding them to the list many times. Furthermore, since commit_lists are stored as linked lists, we must do an O(n) traversal of the list in order to find the right place to insert each commit. This makes building the list O(n^2) in the number of refs. For normal repositories, this isn't a big deal. We have a few hundreds refs at most, and most of them are unique. But consider an "alternates" repo that serves as an object database for many other similar repos. For reachability, it needs to keep a copy of the refs in each child repo. This means it may have a large number of refs, many of which point to the same commits. By noting commits we have already added to the list, we can shrink the size of "n" in such a repo to the number of unique commits, which is on the order of what a normal repo would contain (it's actually more than a normal repo, since child repos may have branches at different states, but in practice it tends to be much smaller than the list with duplicates). Here are the results on one particular giant repo (containing objects for all Rails forks on GitHub): $ git for-each-ref | wc -l 112514 [before] $ git fetch --no-tags ../remote.git 63.52user 0.12system 1:03.68elapsed 99%CPU (0avgtext+0avgdata 137648maxresident)k 1856inputs+48outputs (11major+19603minor)pagefaults 0swaps $ git fetch --no-tags ../remote.git 6.15user 0.08system 0:06.25elapsed 99%CPU (0avgtext+0avgdata 123856maxresident)k 0inputs+40outputs (0major+18872minor)pagefaults 0swaps Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-03-29Merge branch 'jc/fetch-progressive-stride'Junio C Hamano
* jc/fetch-progressive-stride: Fix potential local deadlock during fetch-pack
2011-03-29Merge branches 'sp/maint-fetch-pack-stop-early' and ↵Junio C Hamano
'sp/maint-upload-pack-stop-early' * sp/maint-fetch-pack-stop-early: enable "no-done" extension only when fetching over smart-http * sp/maint-upload-pack-stop-early: enable "no-done" extension only when serving over smart-http