epriestley 7b50b2fbdc Use subprocess output streaming to improve performance of Git commit discovery ... Summary: Improve performance of large discovery tasks in Git by using subprocess streaming, like we do for Mercurial. Basically, we save the cost of running many `git log` commands by running one big `git log` command but only parsing as much of it as we need to. This is pretty complicated, but we more or less need it for mercurial (which has ~100ms of 'hg' overhead instead of ~5ms of 'git' overhead) so we're already committed to most of the complexity costs. The git implementation is much simpler than the hg implementation because we don't need to handle all the weird parent rules (git gives us to them easily). Test Plan: Before, `discover --repair` on Phabricator took 35s: real 0m35.324s user 0m13.364s sys 0m21.088s Now 7s: real 0m7.236s user 0m2.436s sys 0m3.444s Note that most of the time is spent inserting rows after discover, the actual speedup of the git discovery part is much larger (subjectively, it runs in less than a second now, from ~28 seconds before). Also ran discover/pull on single new commits in normal cases to verify that nothing broke in the common case. Reviewers: jungejason, nh, vrana Reviewed By: vrana CC: aran Maniphest Tasks: T1401 Differential Revision: https://secure.phabricator.com/D2851		2012-06-25 15:21:48 -07:00
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__tests__	Move files in Phabricator one level up	2012-06-01 12:32:44 -07:00
PhabricatorGitGraphStream.php	Use subprocess output streaming to improve performance of Git commit discovery	2012-06-25 15:21:48 -07:00
PhabricatorMercurialGraphStream.php	Move files in Phabricator one level up	2012-06-01 12:32:44 -07:00
PhabricatorRepositoryPullLocalDaemon.php	Use subprocess output streaming to improve performance of Git commit discovery	2012-06-25 15:21:48 -07:00