How about fixing @Repository.latest_changesets@, then makes use of it?
See attachment:latest-changesets-improvements.diff

app/models/repository.rb:
* filter by @changes.path = "..." OR changes.path LIKE ".../%"@.
* @JOIN changes@ for path condition; then @SELECT DISTINCT changesets.*@ to strip duplicated records.
* @ORDER BY@ statement are declared by @has_many :changesets, :order => ...@, so no need to specify explicitly.

app/models/repository/subversion.rb:
* use @Repository.latest_changesets@
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Yuya Nishihara wrote:
> See attachment:latest-changesets-improvements.diff

Oops, it has a bug on escaping LIKE pattern. Fixed as attachment:latest-changesets-improvements-2.diff
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Updated Yuya's patch so it uses relative paths for easy patching

(see attachment:latest-changesets-improvements-3.diff)

Usage:

<pre>
cd path/to/your/redmine
patch -p0 < latest-changesets-improvements-3.diff
</pre>
--------------------------------------------------------------------------------

I have updated Yuya's patch as attachment:latest-changesets-improvements-4.diff.

Usage:

<pre>
cd path/to/your/redmine
patch -p1 < latest-changesets-improvements-4.diff
</pre>

The reasons of updating are following.

* Subversion latest_changesets switches "file://" or not.
* Add Mercurial ordering to resolve #3449 and #3567

h2. Subversion latest_changesets switches "file://" or not

Redmine 1.0.4 shows all revisions of *branch* and *tag*.
For example, http://www.redmine.org/projects/redmine/repository/show/tags/1.0.4 shows
r4448 (tagged version 1.0.4), r4447, r4445...
But Yuya's patch shows only r4448.

* attachment:svn-before-patch.png
* attachment:svn-after-patch.png

I have updated as following.

* "file://": use "svn log"
* The others: use only database

It maybe better to be configurable whether using "svn log" or "only database" such as "note-5":http://www.redmine.org/issues/6092#note-5 of #6092.

h2. Improvement of browsing sub directory for other SCMs

This patch improves other SCMs which does not override latest_changesets.
Other SCMs are CVS, Bazaar, Darcs and Mercurial.
Subversion and Git overrides latest_changesets.

Redmine 1.0.4 does not show "latest revisions" of sub directory.
This patch shows it.

Following images are Bazaar images of test repository (source:tags/1.0.4/test/fixtures/repositories/bazaar_repository.tar.gz) .

* attachment:bazaar-before-patch.png
* attachment:bazaar-after-patch.png

h2. Mercurial ordering

Yuya's "hg-changeset-order.patch":http://www.redmine.org/attachments/4218/hg-changeset-order.patch of #4455 overrides Mercurial latest_changesets and add "order by id DESC" to resolve #3449 and #3567.
But, if we apply this patch, we do not need to override it.

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한글로 수정합니다.
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레퍼런스를 관리합니다.

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Fix subject typo.
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relates,New,7984,Confusing revisions links on repository root
relates,Closed,7246,Handle "named branch" for mercurial
relates,New,1311,Subversion: Show revision histories for branches
relates,New,3943,Subversion: Directory revision list contains faulty revisions
relates,New,7528,Fetch small initial set of repository changesets
relates,New,7719,SVN Start Revision