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doc/todo/speed_up___34__standalone_build__34___and__47__or_tests/comment_1_41749c4c9b317a58e02df99f748844a1._comment

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+[[!comment format=mdwn
+ username="joey"
+ subject="""comment 1"""
+ date="2022-03-01T18:06:32Z"
+ content="""
+Since you mentioned standalone builds, I suspect you are running
+something like: "git-annex.linux/git-annex test"
+
+I have verified that is much much slower than running git-annex not
+from the standalone build.
+
+It seems that every time the test suite runs git, it does it via runshell,
+and repeated calls to runshell take time since it has to re-set up the
+standalone environment. This does not happen when the test suite runs
+git-annex; I've verified that its use of programPath results in
+git-annex.linux/bin/git-annex being run, which avoids the runshell
+overhead. 
+
+It looks like the problem is that PATH ends up
+containing "git-annex.linux:git-annex.linux/bin", and so it runs
+the runshell wrapped git. That happens due to setTestMode, which
+appends the current directory to the PATH.
+
+Now, I doubt there would be a real benefit to testing using the standalone
+build, running ./git-annex in the tree where you built it, unless the
+standalone build is made on a system other than the system where the test
+is run. 
+
+But still this repeated runshell is excessive. And should be able to be
+fixed easily now that I've understood it.
+
+However: The main thing I know that will speed up git-annex test generally
+is to parallelize its tests. Which can be done, but needs tasty-1.2. That
+finally made it into debian stable, so it should be able to depend on it
+now. I would not be surprised if it can be sped up 10x that way, because tests
+often have to wait one or more seconds after writing a file due to time
+stamp issues etc. I have created a `paralleltest` branch with a start on
+that, not yet working.
+"""]]