From 7fbbcb21b162883615d5542e06fb2eb8685fd496 Mon Sep 17 00:00:00 2001 From: Jonathan Tan Date: Fri, 5 Apr 2019 10:09:34 -0700 Subject: [PATCH] diff: batch fetching of missing blobs When running a command like "git show" or "git diff" in a partial clone, batch all missing blobs to be fetched as one request. This is similar to c0c578b33c ("unpack-trees: batch fetching of missing blobs", 2017-12-08), but for another command. Signed-off-by: Jonathan Tan Signed-off-by: Junio C Hamano --- diff.c | 34 ++++++++++++++ t/t4067-diff-partial-clone.sh | 103 ++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 137 insertions(+) create mode 100755 t/t4067-diff-partial-clone.sh diff --git a/diff.c b/diff.c index ec5c095199..c5fd9165f9 100644 --- a/diff.c +++ b/diff.c @@ -25,6 +25,7 @@ #include "packfile.h" #include "parse-options.h" #include "help.h" +#include "fetch-object.h" #ifdef NO_FAST_WORKING_DIRECTORY #define FAST_WORKING_DIRECTORY 0 @@ -6366,8 +6367,41 @@ void diffcore_fix_diff_index(void) QSORT(q->queue, q->nr, diffnamecmp); } +static void add_if_missing(struct repository *r, + struct oid_array *to_fetch, + const struct diff_filespec *filespec) +{ + if (filespec && filespec->oid_valid && + oid_object_info_extended(r, &filespec->oid, NULL, + OBJECT_INFO_FOR_PREFETCH)) + oid_array_append(to_fetch, &filespec->oid); +} + void diffcore_std(struct diff_options *options) { + if (options->repo == the_repository && + repository_format_partial_clone) { + /* + * Prefetch the diff pairs that are about to be flushed. + */ + int i; + struct diff_queue_struct *q = &diff_queued_diff; + struct oid_array to_fetch = OID_ARRAY_INIT; + + for (i = 0; i < q->nr; i++) { + struct diff_filepair *p = q->queue[i]; + add_if_missing(options->repo, &to_fetch, p->one); + add_if_missing(options->repo, &to_fetch, p->two); + } + if (to_fetch.nr) + /* + * NEEDSWORK: Consider deduplicating the OIDs sent. + */ + fetch_objects(repository_format_partial_clone, + to_fetch.oid, to_fetch.nr); + oid_array_clear(&to_fetch); + } + /* NOTE please keep the following in sync with diff_tree_combined() */ if (options->skip_stat_unmatch) diffcore_skip_stat_unmatch(options); diff --git a/t/t4067-diff-partial-clone.sh b/t/t4067-diff-partial-clone.sh new file mode 100755 index 0000000000..90c8fb2901 --- /dev/null +++ b/t/t4067-diff-partial-clone.sh @@ -0,0 +1,103 @@ +#!/bin/sh + +test_description='behavior of diff when reading objects in a partial clone' + +. ./test-lib.sh + +test_expect_success 'git show batches blobs' ' + test_when_finished "rm -rf server client trace" && + + test_create_repo server && + echo a >server/a && + echo b >server/b && + git -C server add a b && + git -C server commit -m x && + + test_config -C server uploadpack.allowfilter 1 && + test_config -C server uploadpack.allowanysha1inwant 1 && + git clone --bare --filter=blob:limit=0 "file://$(pwd)/server" client && + + # Ensure that there is exactly 1 negotiation by checking that there is + # only 1 "done" line sent. ("done" marks the end of negotiation.) + GIT_TRACE_PACKET="$(pwd)/trace" git -C client show HEAD && + grep "git> done" trace >done_lines && + test_line_count = 1 done_lines +' + +test_expect_success 'diff batches blobs' ' + test_when_finished "rm -rf server client trace" && + + test_create_repo server && + echo a >server/a && + echo b >server/b && + git -C server add a b && + git -C server commit -m x && + echo c >server/c && + echo d >server/d && + git -C server add c d && + git -C server commit -m x && + + test_config -C server uploadpack.allowfilter 1 && + test_config -C server uploadpack.allowanysha1inwant 1 && + git clone --bare --filter=blob:limit=0 "file://$(pwd)/server" client && + + # Ensure that there is exactly 1 negotiation by checking that there is + # only 1 "done" line sent. ("done" marks the end of negotiation.) + GIT_TRACE_PACKET="$(pwd)/trace" git -C client diff HEAD^ HEAD && + grep "git> done" trace >done_lines && + test_line_count = 1 done_lines +' + +test_expect_success 'diff skips same-OID blobs' ' + test_when_finished "rm -rf server client trace" && + + test_create_repo server && + echo a >server/a && + echo b >server/b && + git -C server add a b && + git -C server commit -m x && + echo another-a >server/a && + git -C server add a && + git -C server commit -m x && + + test_config -C server uploadpack.allowfilter 1 && + test_config -C server uploadpack.allowanysha1inwant 1 && + git clone --bare --filter=blob:limit=0 "file://$(pwd)/server" client && + + echo a | git hash-object --stdin >hash-old-a && + echo another-a | git hash-object --stdin >hash-new-a && + echo b | git hash-object --stdin >hash-b && + + # Ensure that only a and another-a are fetched. + GIT_TRACE_PACKET="$(pwd)/trace" git -C client diff HEAD^ HEAD && + grep "want $(cat hash-old-a)" trace && + grep "want $(cat hash-new-a)" trace && + ! grep "want $(cat hash-b)" trace +' + +test_expect_success 'diff with rename detection batches blobs' ' + test_when_finished "rm -rf server client trace" && + + test_create_repo server && + echo a >server/a && + printf "b\nb\nb\nb\nb\n" >server/b && + git -C server add a b && + git -C server commit -m x && + rm server/b && + printf "b\nb\nb\nb\nbX\n" >server/c && + git -C server add c && + git -C server commit -a -m x && + + test_config -C server uploadpack.allowfilter 1 && + test_config -C server uploadpack.allowanysha1inwant 1 && + git clone --bare --filter=blob:limit=0 "file://$(pwd)/server" client && + + # Ensure that there is exactly 1 negotiation by checking that there is + # only 1 "done" line sent. ("done" marks the end of negotiation.) + GIT_TRACE_PACKET="$(pwd)/trace" git -C client diff -M HEAD^ HEAD >out && + grep "similarity index" out && + grep "git> done" trace >done_lines && + test_line_count = 1 done_lines +' + +test_done -- 2.11.4.GIT