On 12.06.2015 16:55, Philip Martin wrote: > Philip Martin <philip.mar...@wandisco.com> writes: > >> Philip Martin <philip.mar...@wandisco.com> writes: >> >>> 1.9 has a more accurate svn_fs_contents_changed() that doesn't report as >>> many false positives. This means that some (or all?) of the -g revisions >>> reported by svn_repos_get_file_revs2() do not include a textdelta that >>> was included by 1.8. It appears at some level the 1.9 client interprets >>> the revision without a textdelta as being the same as a revision with a >>> textdelta that changes nothing, while the 1.8 client relies on the >>> missing textdelta. If I force the 1.9 server to send textdeltas between >>> identical texts the 1.8 client then behaves as the test expects. >> Looking at r1573111 >> >> /* Check if the contents *may* have changed. (Allow false positives, >> for now, as the blame implementation currently depends on them.) */ >> /* Special case: In the first revision, we always provide a delta. */ >> if (sb->last_root) >> - SVN_ERR(svn_fs_contents_changed2(&contents_changed, sb->last_root, >> - sb->last_path, root, path_rev->path, >> - FALSE, sb->iterpool)); >> + SVN_ERR(svn_fs_contents_different(&contents_changed, sb->last_root, >> + sb->last_path, root, path_rev->path, >> + sb->iterpool)); >> else >> contents_changed = TRUE; >> >> That looks like an error since svn_fs_contents_different() passes TRUE >> for strict, not FALSE. I think the intention was that r1573111 should >> call svn_fs_contents_changed(). >> >> However the implementation of root_vtable_t.contents_changed() has >> changed in 1.9 and it no longer reports as many changes as it used to >> report so even replacing the _different() call with a _changed() call >> does not solve the problem. The only way I can see to fix the problem >> is to simply ignore/remove the call altogether and to hard-code >> contents_changed to TRUE. > This revision is the client-side magic: > > r1570936 | stefan2 | 2014-02-22 22:27:06 +0000 (Sat, 22 Feb 2014) | 10 lines > > Fix the blame -g implemenation to no longer depend on false positives > in the file contents change detection. > > A 1.8 server works with all clients whether they have the fix or not. A > 1.9 server only works when the client has the fix. > > That client-side fix is only in 1.9, so at the moment, only 1.9 clients > work with 1.9 servers.
IMO, the server-side "optimization" should either be reverted, or made dependent on a — probably new — client capability that 1.9 clients (and possibly patched 1.8 clients) can advertise. -- Brane
