From patchwork Thu Oct 26 19:17:51 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zach FettersMoore X-Patchwork-Id: 13437831 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0E2843AC35 for ; Thu, 26 Oct 2023 19:17:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="hkQhPtGL" Received: from mail-wm1-x335.google.com (mail-wm1-x335.google.com [IPv6:2a00:1450:4864:20::335]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A0C3BAC for ; Thu, 26 Oct 2023 12:17:54 -0700 (PDT) Received: by mail-wm1-x335.google.com with SMTP id 5b1f17b1804b1-4084de32db5so10468835e9.0 for ; Thu, 26 Oct 2023 12:17:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1698347873; x=1698952673; darn=vger.kernel.org; h=cc:to:mime-version:content-transfer-encoding:fcc:subject:date:from :references:in-reply-to:message-id:from:to:cc:subject:date :message-id:reply-to; bh=rt6gZ/A9ipUU5cIeB71aTSDEMGNct1rpJz6r6LCgyqs=; b=hkQhPtGLEWok/Hy+4L3Jwq6ncYqf9EK9khDE+pRifQA0glzluKeou3nW+ZmqW1SdvC ivdKlmN3t/RGNRd05pinXM7up0m0DioxruAwMhpuq6vY8TWv0FwEStAyXAgJmYTu4uIE zXSvy9CO9gHNDjRBSimcEd7eflAmBEqsCKjDLdXKfPCj53uh42t7lFQDbCJWkZVLVl42 +hUnRyEeZgf3wbC/GcvLhRZ+2UnmBeAjzo5oovPO5oKAFPEcV4xgPxkvS/ZDdlcATHf0 2SO3pdT3ttg9J1qatCQrAmhAM+H9SpWHJsYfwTXOEaTeELsU/lzDniejtnH70P36IPFW +FXg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1698347873; x=1698952673; h=cc:to:mime-version:content-transfer-encoding:fcc:subject:date:from :references:in-reply-to:message-id:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=rt6gZ/A9ipUU5cIeB71aTSDEMGNct1rpJz6r6LCgyqs=; b=nt1DDBliEKhxBvTp2fciybqA46URVBWZ7RfTlaaU+m/3mty6JQ/Ro409lNFhpRcZGj BFb4DE0zvYb+5JGPoT2nd/TtrR1ra5Ko7VPata0isr7L4eGKjQC4cuxkdzLR9QDP8Rrv OIIEC1e9ES0mlyJRK8zzxhL5pDmWql+T8Q2hTxpaitUxAF6fjzihEYwv8ns86hQjIQci WV/uqNccSlayc5cSHrq2DS1Xvox4nJZ4LXVYXFPyp8hT5EhDFOC2IgRbRtWadGpg0UNv HtpGGUOpQau5guPuLTO4C+v9Ue2Sab7w30QxUecsj1VRNaNoLl6+v1m6dwOfYrWRzw4c w3ig== X-Gm-Message-State: AOJu0Yzl5XOLTBaRyPuPQXU8Lz/rjf5gmnAGaEqrS6VmS3kQhVBBlSQG 1U0DTrL/RXPQzGc5SWyh3Ql1l8PqV8A= X-Google-Smtp-Source: AGHT+IFVADbRxv3NFF+4vrCWnYSQE/VxkQNyMKHevBFjXZ4uYMvIa21svzozeoJhSUN7LzjwPGCwGA== X-Received: by 2002:a05:600c:1547:b0:406:81e9:ad0c with SMTP id f7-20020a05600c154700b0040681e9ad0cmr568787wmg.41.1698347872508; Thu, 26 Oct 2023 12:17:52 -0700 (PDT) Received: from [127.0.0.1] ([13.74.141.28]) by smtp.gmail.com with ESMTPSA id c9-20020a7bc849000000b00405d9a950a2sm3250320wml.28.2023.10.26.12.17.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 26 Oct 2023 12:17:52 -0700 (PDT) Message-ID: In-Reply-To: References: Date: Thu, 26 Oct 2023 19:17:51 +0000 Subject: [PATCH v4] subtree: fix split processing with multiple subtrees present Fcc: Sent Precedence: bulk X-Mailing-List: git@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 To: git@vger.kernel.org Cc: Zach FettersMoore , Zach FettersMoore From: Zach FettersMoore From: Zach FettersMoore When there are multiple subtrees present in a repository and they are all using 'git subtree split', the 'split' command can take a significant (and constantly growing) amount of time to run even when using the '--rejoin' flag. This is due to the fact that when processing commits to determine the last known split to start from when looking for changes, if there has been a split/merge done from another subtree there will be 2 split commits, one mainline and one subtree, for the second subtree that are part of the processing. The non-mainline subtree split commit will cause the processing to always need to search the entire history of the given subtree as part of its processing even though those commits are totally irrelevant to the current subtree split being run. In the diagram below, 'M' represents the mainline repo branch, 'A' represents one subtree, and 'B' represents another. M3 and B1 represent a split commit for subtree B that was created from commit M4. M2 and A1 represent a split commit made from subtree A that was also created based on changes back to and including M4. M1 represents new changes to the repo, in this scenario if you try to run a 'git subtree split --rejoin' for subtree B, commits M1, M2, and A1, will be included in the processing of changes for the new split commit since the last split/rejoin for subtree B was at M3. The issue is that by having A1 included in this processing the command ends up needing to processing every commit down tree A even though none of that is needed or relevant to the current command and result. M1 | \ \ M2 | | | A1 | M3 | | | | B1 M4 | | So this commit makes a change to the processing of commits for the split command in order to ignore non-mainline commits from other subtrees such as A1 in the diagram by adding a new function 'should_ignore_subtree_commit' which is called during 'process_split_commit'. This allows the split/rejoin processing to still function as expected but removes all of the unnecessary processing that takes place currently which greatly inflates the processing time. Added a test to validate that the proposed fix solves the issue. The test accomplishes this by checking the output of the split command to ensure the output from the progress of 'process_split_commit' function that represents the 'extracount' of commits processed does not increment. This was tested against the original functionality to show the test failed, and then with this fix to show the test passes. This illustrated that when using multiple subtrees, A and B, when doing a split on subtree B, the processing does not traverse the entire history of subtree A which is unnecessary and would cause the 'extracount' of processed commits to climb based on the number of commits in the history of subtree A. Signed-off-by: Zach FettersMoore --- subtree: fix split processing with multiple subtrees present When there are multiple subtrees in a repo and git subtree split --rejoin is being used for the subtrees, the processing of commits for a new split can take a significant (and constantly growing) amount of time because the split commits from other subtrees cause the processing to have to scan the entire history of the other subtree(s). This patch filters out the other subtree split commits that are unnecessary for the split commit processing. Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-1587%2FBobaFetters%2Fzf%2Fmulti-subtree-processing-v4 Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-1587/BobaFetters/zf/multi-subtree-processing-v4 Pull-Request: https://github.com/gitgitgadget/git/pull/1587 Range-diff vs v3: 1: 43175154a82 < -: ----------- subtree: fix split processing with multiple subtrees present 2: d6811daf7cf < -: ----------- subtree: changing location of commit ignore processing 3: eff8bfcc042 ! 1: 353152910eb subtree: adding test to validate fix @@ Metadata Author: Zach FettersMoore ## Commit message ## - subtree: adding test to validate fix + subtree: fix split processing with multiple subtrees present - Adding a test to validate that the proposed fix + When there are multiple subtrees present in a repository and they are + all using 'git subtree split', the 'split' command can take a + significant (and constantly growing) amount of time to run even when + using the '--rejoin' flag. This is due to the fact that when processing + commits to determine the last known split to start from when looking + for changes, if there has been a split/merge done from another subtree + there will be 2 split commits, one mainline and one subtree, for the + second subtree that are part of the processing. The non-mainline + subtree split commit will cause the processing to always need to search + the entire history of the given subtree as part of its processing even + though those commits are totally irrelevant to the current subtree + split being run. + + In the diagram below, 'M' represents the mainline repo branch, 'A' + represents one subtree, and 'B' represents another. M3 and B1 represent + a split commit for subtree B that was created from commit M4. M2 and A1 + represent a split commit made from subtree A that was also created + based on changes back to and including M4. M1 represents new changes to + the repo, in this scenario if you try to run a 'git subtree split + --rejoin' for subtree B, commits M1, M2, and A1, will be included in + the processing of changes for the new split commit since the last + split/rejoin for subtree B was at M3. The issue is that by having A1 + included in this processing the command ends up needing to processing + every commit down tree A even though none of that is needed or relevant + to the current command and result. + + M1 + | \ \ + M2 | | + | A1 | + M3 | | + | | B1 + M4 | | + + So this commit makes a change to the processing of commits for the split + command in order to ignore non-mainline commits from other subtrees such + as A1 in the diagram by adding a new function + 'should_ignore_subtree_commit' which is called during + 'process_split_commit'. This allows the split/rejoin processing to still + function as expected but removes all of the unnecessary processing that + takes place currently which greatly inflates the processing time. + + Added a test to validate that the proposed fix solves the issue. The test accomplishes this by checking the output @@ Commit message Signed-off-by: Zach FettersMoore + ## contrib/subtree/git-subtree.sh ## +@@ contrib/subtree/git-subtree.sh: ensure_valid_ref_format () { + die "fatal: '$1' does not look like a ref" + } + ++# Usage: check if a commit from another subtree should be ++# ignored from processing for splits ++should_ignore_subtree_split_commit () { ++ if test -n "$(git log -1 --grep="git-subtree-dir:" $1)" ++ then ++ if test -z "$(git log -1 --grep="git-subtree-mainline:" $1)" && ++ test -z "$(git log -1 --grep="git-subtree-dir: $arg_prefix$" $1)" ++ then ++ return 0 ++ fi ++ fi ++ return 1 ++} ++ + # Usage: process_split_commit REV PARENTS + process_split_commit () { + assert test $# = 2 +@@ contrib/subtree/git-subtree.sh: cmd_split () { + eval "$grl" | + while read rev parents + do +- process_split_commit "$rev" "$parents" ++ if should_ignore_subtree_split_commit "$rev" ++ then ++ continue ++ fi ++ parsedParents='' ++ for parent in $parents ++ do ++ should_ignore_subtree_split_commit "$parent" ++ if test $? -eq 1 ++ then ++ parsedParents+="$parent " ++ fi ++ done ++ process_split_commit "$rev" "$parsedParents" + done || exit $? + + latest_new=$(cache_get latest_new) || exit $? + ## contrib/subtree/t/t7900-subtree.sh ## @@ contrib/subtree/t/t7900-subtree.sh: test_expect_success 'split sub dir/ with --rejoin' ' ) @@ contrib/subtree/t/t7900-subtree.sh: test_expect_success 'split sub dir/ with --r + ) && + ( + cd "$test_count" && -+ test "$(git subtree split --prefix=subBDir --squash --rejoin -d -m "Sub B Split 1" 2>&1 | grep -w "\[1\]")" = "" ++ test "$(git subtree split --prefix=subBDir --squash --rejoin \ ++ -d -m "Sub B Split 1" 2>&1 | grep -w "\[1\]")" = "" + ) +' + contrib/subtree/git-subtree.sh | 29 ++++++++++++++++++++- contrib/subtree/t/t7900-subtree.sh | 42 ++++++++++++++++++++++++++++++ 2 files changed, 70 insertions(+), 1 deletion(-) base-commit: bda494f4043963b9ec9a1ecd4b19b7d1cd9a0518 diff --git a/contrib/subtree/git-subtree.sh b/contrib/subtree/git-subtree.sh index e0c5d3b0de6..e69991a9d80 100755 --- a/contrib/subtree/git-subtree.sh +++ b/contrib/subtree/git-subtree.sh @@ -778,6 +778,20 @@ ensure_valid_ref_format () { die "fatal: '$1' does not look like a ref" } +# Usage: check if a commit from another subtree should be +# ignored from processing for splits +should_ignore_subtree_split_commit () { + if test -n "$(git log -1 --grep="git-subtree-dir:" $1)" + then + if test -z "$(git log -1 --grep="git-subtree-mainline:" $1)" && + test -z "$(git log -1 --grep="git-subtree-dir: $arg_prefix$" $1)" + then + return 0 + fi + fi + return 1 +} + # Usage: process_split_commit REV PARENTS process_split_commit () { assert test $# = 2 @@ -963,7 +977,20 @@ cmd_split () { eval "$grl" | while read rev parents do - process_split_commit "$rev" "$parents" + if should_ignore_subtree_split_commit "$rev" + then + continue + fi + parsedParents='' + for parent in $parents + do + should_ignore_subtree_split_commit "$parent" + if test $? -eq 1 + then + parsedParents+="$parent " + fi + done + process_split_commit "$rev" "$parsedParents" done || exit $? latest_new=$(cache_get latest_new) || exit $? diff --git a/contrib/subtree/t/t7900-subtree.sh b/contrib/subtree/t/t7900-subtree.sh index 49a21dd7c9c..87d59afd761 100755 --- a/contrib/subtree/t/t7900-subtree.sh +++ b/contrib/subtree/t/t7900-subtree.sh @@ -385,6 +385,48 @@ test_expect_success 'split sub dir/ with --rejoin' ' ) ' +test_expect_success 'split with multiple subtrees' ' + subtree_test_create_repo "$test_count" && + subtree_test_create_repo "$test_count/subA" && + subtree_test_create_repo "$test_count/subB" && + test_create_commit "$test_count" main1 && + test_create_commit "$test_count/subA" subA1 && + test_create_commit "$test_count/subA" subA2 && + test_create_commit "$test_count/subA" subA3 && + test_create_commit "$test_count/subB" subB1 && + ( + cd "$test_count" && + git fetch ./subA HEAD && + git subtree add --prefix=subADir FETCH_HEAD + ) && + ( + cd "$test_count" && + git fetch ./subB HEAD && + git subtree add --prefix=subBDir FETCH_HEAD + ) && + test_create_commit "$test_count" subADir/main-subA1 && + test_create_commit "$test_count" subBDir/main-subB1 && + ( + cd "$test_count" && + git subtree split --prefix=subADir --squash --rejoin -m "Sub A Split 1" + ) && + ( + cd "$test_count" && + git subtree split --prefix=subBDir --squash --rejoin -m "Sub B Split 1" + ) && + test_create_commit "$test_count" subADir/main-subA2 && + test_create_commit "$test_count" subBDir/main-subB2 && + ( + cd "$test_count" && + git subtree split --prefix=subADir --squash --rejoin -m "Sub A Split 2" + ) && + ( + cd "$test_count" && + test "$(git subtree split --prefix=subBDir --squash --rejoin \ + -d -m "Sub B Split 1" 2>&1 | grep -w "\[1\]")" = "" + ) +' + test_expect_success 'split sub dir/ with --rejoin from scratch' ' subtree_test_create_repo "$test_count" && test_create_commit "$test_count" main1 &&