From patchwork Thu Mar 3 00:21:12 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Taylor Blau X-Patchwork-Id: 12766914 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3B190C433EF for ; Thu, 3 Mar 2022 00:21:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230303AbiCCAWO (ORCPT ); Wed, 2 Mar 2022 19:22:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39368 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230309AbiCCAWE (ORCPT ); Wed, 2 Mar 2022 19:22:04 -0500 Received: from mail-qk1-x730.google.com (mail-qk1-x730.google.com [IPv6:2607:f8b0:4864:20::730]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 00681108BEB for ; Wed, 2 Mar 2022 16:21:14 -0800 (PST) Received: by mail-qk1-x730.google.com with SMTP id j78so2765168qke.2 for ; Wed, 02 Mar 2022 16:21:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ttaylorr-com.20210112.gappssmtp.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=UPxwnco55y3KVMik+Hig4ofVjW1qyYM1nMSvNCw2Bc4=; b=Rb8ikzNZttyz1Ozd3L3fyR4807WomaGo+dtaQGkbza++76io7JAwaabUlI1P2XpiZ9 ZbAWgi/golZUzMyuFcODNmpXI43gQ9NrRMXNbpGyGQ7Ah8tZotCtT3//iGkOeoQZa7J2 lVVvskSnqqF+mGG8l8lOrJhuxp2t9bzLTdoO87+fyxRVNejuXLbBcL11Ep0M7JtoF3ay H68JevjQ7QyJuZgChiZNskqC9a5vgzs5D9o5J4hzukqzg7au0KBNz372ceyJHvx4/Bwx odFIXLSin6D6WsX41IdsmX21QnA5WcKAEwHHq/m5FzpwSJNX/xtsobQXsKWDLLABjf13 vmug== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=UPxwnco55y3KVMik+Hig4ofVjW1qyYM1nMSvNCw2Bc4=; b=AfQl69WaHvc3Z+SjwdmbrkQytJblPUTPllCzTARdX5dgaSV0Df+TwS3EIKtWKXtbzv LMzOuE8H5vnc3CYmkmtyOAkvEYYy5Tsw5nC+bu7bvEWNyekzjQ4rI2/7zYi4kPQc3lW8 Xn4a2ZM17IUGic+SU/4d5jJYJvMEcBawxnzAYr1mYTytQRir9dmCzer4g+YVWW2vv5MD u1zXVzPBFVhKp6aqV8QzJ6YgBbrEM5OtXOjn0ru2I3Gwm6sSkq469HchsLhAH1jF61r9 KE6WyfnwN6RA+ZB3208fYulgM+rHQ16gGftdEDukdzlCf+RQn84lsHdhYVCERKlHUIcS Mp3A== X-Gm-Message-State: AOAM530MxgAOOEpFXMKRRNLaRzU6Lvd6VGk5EFmYFkV257wyRyULanBr o80702xas51B8Iiq06PivZC7S7Y3R1LaVWoN X-Google-Smtp-Source: ABdhPJxgN/+lv7jvFjFliUoX2ZZTHrAR+fH9WB94T8coHN+9mODRNieKqB1vwR3erHRz2HNIcLNgcA== X-Received: by 2002:a37:a487:0:b0:60d:d3a1:a660 with SMTP id n129-20020a37a487000000b0060dd3a1a660mr17653397qke.178.1646266873730; Wed, 02 Mar 2022 16:21:13 -0800 (PST) Received: from localhost (104-178-186-189.lightspeed.milwwi.sbcglobal.net. [104.178.186.189]) by smtp.gmail.com with ESMTPSA id o18-20020a05620a111200b00508188ead26sm293120qkk.97.2022.03.02.16.21.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 02 Mar 2022 16:21:13 -0800 (PST) Date: Wed, 2 Mar 2022 19:21:12 -0500 From: Taylor Blau To: git@vger.kernel.org Cc: tytso@mit.edu, derrickstolee@github.com, gitster@pobox.com, larsxschneider@gmail.com Subject: [PATCH v3 12/17] builtin/repack.c: support generating a cruft pack Message-ID: <1e94b33cb4d9f3e1f29ef754a9cc09898779836a.1646266835.git.me@ttaylorr.com> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Expose a way to split the contents of a repository into a main and cruft pack when doing an all-into-one repack with `git repack --cruft -d`, and a complementary configuration variable. Signed-off-by: Taylor Blau --- Documentation/git-repack.txt | 11 ++ Documentation/technical/cruft-packs.txt | 2 +- builtin/repack.c | 106 +++++++++++- t/t5329-pack-objects-cruft.sh | 207 ++++++++++++++++++++++++ 4 files changed, 320 insertions(+), 6 deletions(-) diff --git a/Documentation/git-repack.txt b/Documentation/git-repack.txt index ee30edc178..0bf13893d8 100644 --- a/Documentation/git-repack.txt +++ b/Documentation/git-repack.txt @@ -63,6 +63,17 @@ to the new separate pack will be written. Also run 'git prune-packed' to remove redundant loose object files. +--cruft:: + Same as `-a`, unless `-d` is used. Then any unreachable objects + are packed into a separate cruft pack. Unreachable objects can + be pruned using the normal expiry rules with the next `git gc` + invocation (see linkgit:git-gc[1]). Incompatible with `-k`. + +--cruft-expiration=:: + Expire unreachable objects older than `` + immediately instead of waiting for the next `git gc` invocation. + Only useful with `--cruft -d`. + -l:: Pass the `--local` option to 'git pack-objects'. See linkgit:git-pack-objects[1]. diff --git a/Documentation/technical/cruft-packs.txt b/Documentation/technical/cruft-packs.txt index 2c3c5d93f8..f80e975a47 100644 --- a/Documentation/technical/cruft-packs.txt +++ b/Documentation/technical/cruft-packs.txt @@ -17,7 +17,7 @@ pruned according to normal expiry rules with the next 'git gc' invocation. Unreachable objects aren't removed immediately, since doing so could race with an incoming push which may reference an object which is about to be deleted. -Instead, those unreachable objects are stored as loose object and stay that way +Instead, those unreachable objects are stored as loose objects and stay that way until they are older than the expiration window, at which point they are removed by linkgit:git-prune[1]. diff --git a/builtin/repack.c b/builtin/repack.c index f908f7d5dd..f7fb88bcf1 100644 --- a/builtin/repack.c +++ b/builtin/repack.c @@ -18,11 +18,17 @@ #include "pack-bitmap.h" #include "refs.h" +#define ALL_INTO_ONE 1 +#define LOOSEN_UNREACHABLE 2 +#define PACK_CRUFT 4 + +static int pack_everything; static int delta_base_offset = 1; static int pack_kept_objects = -1; static int write_bitmaps = -1; static int use_delta_islands; static char *packdir, *packtmp_name, *packtmp; +static char *cruft_expiration; static const char *const git_repack_usage[] = { N_("git repack []"), @@ -54,6 +60,7 @@ static int repack_config(const char *var, const char *value, void *cb) use_delta_islands = git_config_bool(var, value); return 0; } + return git_default_config(var, value, cb); } @@ -300,9 +307,6 @@ static void repack_promisor_objects(const struct pack_objects_args *args, die(_("could not finish pack-objects to repack promisor objects")); } -#define ALL_INTO_ONE 1 -#define LOOSEN_UNREACHABLE 2 - struct pack_geometry { struct packed_git **pack; uint32_t pack_nr, pack_alloc; @@ -339,6 +343,8 @@ static void init_pack_geometry(struct pack_geometry **geometry_p) for (p = get_all_packs(the_repository); p; p = p->next) { if (!pack_kept_objects && p->pack_keep) continue; + if (p->is_cruft) + continue; ALLOC_GROW(geometry->pack, geometry->pack_nr + 1, @@ -600,6 +606,67 @@ static int write_midx_included_packs(struct string_list *include, return finish_command(&cmd); } +static int write_cruft_pack(const struct pack_objects_args *args, + const char *pack_prefix, + struct string_list *names, + struct string_list *existing_packs, + struct string_list *existing_kept_packs) +{ + struct child_process cmd = CHILD_PROCESS_INIT; + struct strbuf line = STRBUF_INIT; + struct string_list_item *item; + FILE *in, *out; + int ret; + + prepare_pack_objects(&cmd, args); + + strvec_push(&cmd.args, "--cruft"); + if (cruft_expiration) + strvec_pushf(&cmd.args, "--cruft-expiration=%s", + cruft_expiration); + + strvec_push(&cmd.args, "--honor-pack-keep"); + strvec_push(&cmd.args, "--non-empty"); + strvec_push(&cmd.args, "--max-pack-size=0"); + + cmd.in = -1; + + ret = start_command(&cmd); + if (ret) + return ret; + + /* + * names has a confusing double use: it both provides the list + * of just-written new packs, and accepts the name of the cruft + * pack we are writing. + * + * By the time it is read here, it contains only the pack(s) + * that were just written, which is exactly the set of packs we + * want to consider kept. + */ + in = xfdopen(cmd.in, "w"); + for_each_string_list_item(item, names) + fprintf(in, "%s-%s.pack\n", pack_prefix, item->string); + for_each_string_list_item(item, existing_packs) + fprintf(in, "-%s.pack\n", item->string); + for_each_string_list_item(item, existing_kept_packs) + fprintf(in, "%s.pack\n", item->string); + fclose(in); + + out = xfdopen(cmd.out, "r"); + while (strbuf_getline_lf(&line, out) != EOF) { + if (line.len != the_hash_algo->hexsz) + die(_("repack: Expecting full hex object ID lines only " + "from pack-objects.")); + string_list_append(names, line.buf); + } + fclose(out); + + strbuf_release(&line); + + return finish_command(&cmd); +} + int cmd_repack(int argc, const char **argv, const char *prefix) { struct child_process cmd = CHILD_PROCESS_INIT; @@ -616,7 +683,6 @@ int cmd_repack(int argc, const char **argv, const char *prefix) int show_progress; /* variables to be filled by option parsing */ - int pack_everything = 0; int delete_redundant = 0; const char *unpack_unreachable = NULL; int keep_unreachable = 0; @@ -632,6 +698,11 @@ int cmd_repack(int argc, const char **argv, const char *prefix) OPT_BIT('A', NULL, &pack_everything, N_("same as -a, and turn unreachable objects loose"), LOOSEN_UNREACHABLE | ALL_INTO_ONE), + OPT_BIT(0, "cruft", &pack_everything, + N_("same as -a, pack unreachable cruft objects separately"), + PACK_CRUFT), + OPT_STRING(0, "cruft-expiration", &cruft_expiration, N_("approxidate"), + N_("with -C, expire objects older than this")), OPT_BOOL('d', NULL, &delete_redundant, N_("remove redundant packs, and run git-prune-packed")), OPT_BOOL('f', NULL, &po_args.no_reuse_delta, @@ -684,6 +755,15 @@ int cmd_repack(int argc, const char **argv, const char *prefix) (unpack_unreachable || (pack_everything & LOOSEN_UNREACHABLE))) die(_("options '%s' and '%s' cannot be used together"), "--keep-unreachable", "-A"); + if (pack_everything & PACK_CRUFT) { + pack_everything |= ALL_INTO_ONE; + + if (unpack_unreachable || (pack_everything & LOOSEN_UNREACHABLE)) + die(_("options '%s' and '%s' cannot be used together"), "--cruft", "-A"); + if (keep_unreachable) + die(_("options '%s' and '%s' cannot be used together"), "--cruft", "-k"); + } + if (write_bitmaps < 0) { if (!write_midx && (!(pack_everything & ALL_INTO_ONE) || !is_bare_repository())) @@ -767,7 +847,8 @@ int cmd_repack(int argc, const char **argv, const char *prefix) if (pack_everything & ALL_INTO_ONE) { repack_promisor_objects(&po_args, &names); - if (existing_nonkept_packs.nr && delete_redundant) { + if (existing_nonkept_packs.nr && delete_redundant && + !(pack_everything & PACK_CRUFT)) { for_each_string_list_item(item, &names) { strvec_pushf(&cmd.args, "--keep-pack=%s-%s.pack", packtmp_name, item->string); @@ -829,6 +910,21 @@ int cmd_repack(int argc, const char **argv, const char *prefix) if (!names.nr && !po_args.quiet) printf_ln(_("Nothing new to pack.")); + if (pack_everything & PACK_CRUFT) { + const char *pack_prefix; + if (!skip_prefix(packtmp, packdir, &pack_prefix)) + die(_("pack prefix %s does not begin with objdir %s"), + packtmp, packdir); + if (*pack_prefix == '/') + pack_prefix++; + + ret = write_cruft_pack(&po_args, pack_prefix, &names, + &existing_nonkept_packs, + &existing_kept_packs); + if (ret) + return ret; + } + for_each_string_list_item(item, &names) { item->util = (void *)(uintptr_t)populate_pack_exts(item->string); } diff --git a/t/t5329-pack-objects-cruft.sh b/t/t5329-pack-objects-cruft.sh index 939cdc297a..06c550c958 100755 --- a/t/t5329-pack-objects-cruft.sh +++ b/t/t5329-pack-objects-cruft.sh @@ -358,4 +358,211 @@ test_expect_success 'expired objects are pruned' ' ) ' +test_expect_success 'repack --cruft generates a cruft pack' ' + git init repo && + test_when_finished "rm -fr repo" && + ( + cd repo && + + test_commit reachable && + git branch -M main && + git checkout --orphan other && + test_commit unreachable && + + git checkout main && + git branch -D other && + git tag -d unreachable && + # objects are not cruft if they are contained in the reflogs + git reflog expire --all --expire=all && + + git rev-list --objects --all --no-object-names >reachable.raw && + git cat-file --batch-all-objects --batch-check="%(objectname)" >objects && + sort reachable && + comm -13 reachable objects >unreachable && + + git repack --cruft -d && + + cruft=$(basename $(ls $packdir/pack-*.mtimes) .mtimes) && + pack=$(basename $(ls $packdir/pack-*.pack | grep -v $cruft) .pack) && + + git show-index <$packdir/$pack.idx >actual.raw && + cut -f2 -d" " actual.raw | sort >actual && + test_cmp reachable actual && + + git show-index <$packdir/$cruft.idx >actual.raw && + cut -f2 -d" " actual.raw | sort >actual && + test_cmp unreachable actual + ) +' + +test_expect_success 'loose objects mtimes upsert others' ' + git init repo && + test_when_finished "rm -fr repo" && + ( + cd repo && + + test_commit reachable && + git repack -Ad && + git branch -M main && + + git checkout --orphan other && + test_commit cruft && + # incremental repack, leaving existing objects loose (so + # they can be "freshened") + git repack && + + tip="$(git rev-parse cruft)" && + path="$objdir/$(test_oid_to_path "$(git rev-parse cruft)")" && + test-tool chmtime --get +1000 "$path" >expect && + + git checkout main && + git branch -D other && + git tag -d cruft && + git reflog expire --all --expire=all && + + git repack --cruft -d && + + mtimes="$(basename $(ls $packdir/pack-*.mtimes))" && + test-tool pack-mtimes "$mtimes" >actual.raw && + grep "$tip" actual.raw | cut -d" " -f2 >actual && + test_cmp expect actual + ) +' + +test_expect_success 'cruft packs are not included in geometric repack' ' + git init repo && + test_when_finished "rm -fr repo" && + ( + cd repo && + + test_commit reachable && + git repack -Ad && + git branch -M main && + + git checkout --orphan other && + test_commit cruft && + git repack -d && + + git checkout main && + git branch -D other && + git tag -d cruft && + git reflog expire --all --expire=all && + + git repack --cruft && + + find $packdir -type f | sort >before && + git repack --geometric=2 -d && + find $packdir -type f | sort >after && + + test_cmp before after + ) +' + +test_expect_success 'repack --geometric collects once-cruft objects' ' + git init repo && + test_when_finished "rm -fr repo" && + ( + cd repo && + + test_commit reachable && + git repack -Ad && + git branch -M main && + + git checkout --orphan other && + git rm -rf . && + test_commit --no-tag cruft && + cruft="$(git rev-parse HEAD)" && + + git checkout main && + git branch -D other && + git reflog expire --all --expire=all && + + # Pack the objects created in the previous step into a cruft + # pack. Intentionally leave loose copies of those objects + # around so we can pick them up in a subsequent --geometric + # reapack. + git repack --cruft && + + # Now make those objects reachable, and ensure that they are + # packed into the new pack created via a --geometric repack. + git update-ref refs/heads/other $cruft && + + # Without this object, the set of unpacked objects is exactly + # the set of objects already in the cruft pack. Tweak that set + # to ensure we do not overwrite the cruft pack entirely. + test_commit reachable2 && + + find $packdir -name "pack-*.idx" | sort >before && + git repack --geometric=2 -d && + find $packdir -name "pack-*.idx" | sort >after && + + { + git rev-list --objects --no-object-names $cruft && + git rev-list --objects --no-object-names reachable..reachable2 + } >want.raw && + sort want.raw >want && + + pack=$(comm -13 before after) && + git show-index <$pack >objects.raw && + + cut -d" " -f2 objects.raw | sort >got && + + test_cmp want got + ) +' + +test_expect_success 'cruft repack with no reachable objects' ' + git init repo && + test_when_finished "rm -fr repo" && + ( + cd repo && + + test_commit base && + git repack -ad && + + base="$(git rev-parse base)" && + + git for-each-ref --format="delete %(refname)" >in && + git update-ref --stdin cruft && + test_line_count = 1 cruft && + test-tool pack-mtimes "$(basename "$(cat cruft)")" >objects && + test_line_count = 2 objects + ) +' + +test_expect_success 'cruft repack ignores pack.packSizeLimit' ' + ( + cd max-pack-size && + # repack everything back together to remove the existing cruft + # pack (but to keep its objects) + git repack -adk && + git -c pack.packSizeLimit=1M repack --cruft && + # ensure the same post condition is met when --max-pack-size + # would otherwise be inferred from the configuration + find $packdir -name "*.mtimes" >cruft && + test_line_count = 1 cruft && + test-tool pack-mtimes "$(basename "$(cat cruft)")" >objects && + test_line_count = 2 objects + ) +' + test_done