Re: [jgit-dev] ObjectDirectory.scanPacksImpl performance regression and

[Thomas Wolf <thomas.wolf@xxxxxxxxxx>]

Hi Marc,

On 22 May 2019, at 19:24 , Marc Strapetz <marc.strapetz@xxxxxxxxxxx> wrote:

With commits 82b1af31 and fef78212, the reuse condition of existing PackFiles in ObjectDirectory.scanPacksImpl has been changed

[...]

Due to the racy-clean handling in FileSnapshot.isModified, this results in many false-positive modification detections immediately after creating or modifying a PackFile and thus in redundant re-creation of PackFiles. I'm experiencing our unit tests to be ~5x slower with this change.

Yes, that's bug 546891: https://bugs.eclipse.org/bugs/show_bug.cgi?id=546891 We're trying to fix it. See the chain of changes at https://git.eclipse.org/r/#/c/141843/ .

Also, the oldPack may now be removed from "forReuse" and thus not properly closed anymore further down the loop.

That bit got missed. Thanks for pointing it out.

Cheers,

  Thomas