kernel/git - git - PowerEL Git System

Author	SHA1	Message	Date
Derrick Stolee	de3a864114	config: set pack.useSparse=true by default The pack.useSparse config option was introduced by `3d036eb0` (pack-objects: create pack.useSparse setting, 2019-01-19) and was first available in v2.21.0. When enabled, the pack-objects process during 'git push' will use a sparse tree walk when deciding which trees and blobs to send to the remote. The algorithm was introduced by `d5d2e93` (revision: implement sparse algorithm, 2019-01-16) and has been in production use by VFS for Git since around that time. The features.experimental config option also enabled pack.useSparse, so hopefully that has also increased exposure. It is worth noting that pack.useSparse has a possibility of sending more objects across a push, but requires a special arrangement of exact _copies_ across directories. There is a test in t5322-pack-objects-sparse.sh that demonstrates this possibility. This test uses the --sparse option to "git pack-objects" but we can make it implied by the config value to demonstrate that the default value has changed. While updating that test, I noticed that the documentation did not include an option for --no-sparse, which is now more important than it was before. Since the downside is unlikely but the upside is significant, set the default value of pack.useSparse to true. Remove it from the set of options implied by features.experimental. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>	5 years ago
Jeff King	e704fc7978	pack-objects: introduce pack.allowPackReuse Let's make it possible to configure if we want pack reuse or not. The main reason it might not be wanted is probably debugging and performance testing, though pack reuse _might_ cause larger packs, because we wouldn't consider the reused objects as bases for finding new deltas. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>	5 years ago
Derrick Stolee	aaf633c2ad	repo-settings: create feature.experimental setting The 'feature.experimental' setting includes config options that are not committed to become defaults, but could use additional testing. Update the following config settings to take new defaults, and to use the repo_settings struct if not already using them: * 'pack.useSparse=true' * 'fetch.negotiationAlgorithm=skipping' In the case of fetch.negotiationAlgorithm, the existing logic would load the config option only when about to use the setting, so had a die() statement on an unknown string value. This is removed as now the config is parsed under prepare_repo_settings(). In general, this die() is probably misplaced and not valuable. A test was removed that checked this die() statement executed. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>	6 years ago
Jeff King	d4316604f8	pack-objects: default to writing bitmap hash-cache Enabling pack.writebitmaphashcache should always be a performance win. It costs only 4 bytes per object on disk, and the timings in `ae4f07fbcc` (pack-bitmap: implement optional name_hash cache, 2013-12-21) show it improving fetch and partial-bitmap clone times by 40-50%. The only reason we didn't enable it by default at the time is that early versions of JGit's bitmap reader complained about the presence of optional header bits it didn't understand. But that was changed in JGit's d2fa3987a (Use bitcheck to check for presence of OPT_FULL option, 2013-10-30), which made it into JGit v3.5.0 in late 2014. So let's turn this option on by default. It's backwards-compatible with all versions of Git, and if you are also using JGit on the same repository, you'd only run into problems using a version that's almost 5 years old. We'll drop the manual setting from all of our test scripts, including perf tests. This isn't strictly necessary, but it has two advantages: 1. If the hash-cache ever stops being enabled by default, our perf regression tests will notice. 2. We can use the modified perf tests to show off the behavior of an otherwise unconfigured repo, as shown below. These are the results of a few of a perf tests against linux.git that showed interesting results. You can see the expected speedup in 5310.4, which was noted in `ae4f07fbcc`. Curiously, 5310.8 did not improve (and actually got slower), despite seeing the opposite in `ae4f07fbcc`. I don't have an explanation for that. The tests from p5311 did not exist back then, but do show improvements (a smaller pack due to better deltas, which we found in less time). Test HEAD^ HEAD ------------------------------------------------------------------------------------- 5310.4: simulated fetch 7.39(22.70+0.25) 5.64(11.43+0.22) -23.7% 5310.8: clone (partial bitmap) 18.45(24.83+1.19) 19.94(28.40+1.36) +8.1% 5311.31: server (128 days) 0.41(1.13+0.05) 0.34(0.72+0.02) -17.1% 5311.32: size (128 days) 7.4M 7.0M -4.8% 5311.33: client (128 days) 1.33(1.49+0.06) 1.29(1.37+0.12) -3.0% Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>	6 years ago
Derrick Stolee	3d036eb0d2	pack-objects: create pack.useSparse setting The '--sparse' flag in 'git pack-objects' changes the algorithm used to enumerate objects to one that is faster for individual users pushing new objects that change only a small cone of the working directory. The sparse algorithm is not recommended for a server, which likely sends new objects that appear across the entire working directory. Create a 'pack.useSparse' setting that enables this new algorithm. This allows 'git push' to use this algorithm without passing a '--sparse' flag all the way through four levels of run_command() calls. If the '--no-sparse' flag is set, then this config setting is overridden. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>	6 years ago
Nguyễn Thái Ngọc Duy	a168c5a2cd	config.txt: move pack.* to a separate file Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>	6 years ago