mercurial: Changelog

exchange: support transferring .hgtags fnodes mapping On Mozilla's mozilla-beta repository .hgtags fnodes resolution takes ~18s from a clean cache on my machine. This means that the first time a user runs `hg tags`, `hg log`, or any other command that displays or accesses tags data, a ~18s pause will occur. There is no output during this pause. This results in a poor user experience and perception that Mercurial is slow. The .hgtags changeset to filenode mapping is deterministic. This patch takes advantage of that property by implementing support for transferring .hgtags filenodes mappings in a dedicated bundle2 part. When a client advertising support for the "hgtagsfnodes" capability requests a bundle, a mapping of changesets to .hgtags filenodes will be sent to the client. Only mappings of head changesets included in the bundle will be sent. The transfer of this mapping effectively eliminates one time tags cache related pauses after initial clone. The mappings are sent as binary data. So, 40 bytes per pair of SHA-1s. On the aforementioned mozilla-beta repository, 659 * 40 = 26,360 raw bytes of mappings are sent over the wire (in addition to the bundle part headers). Assuming 18s to populate the cache, we only need to transfer this extra data faster than 1.5 KB/s for overall clone + tags cache population time to be shorter. Put into perspective, the mozilla-beta repository is ~1 GB in size. So, this additional data constitutes <0.01% of the cloned data. The marginal overhead for a multi-second performance win on clones in my opinion justifies an on-by-default behavior.

bundle2: part handler for processing .hgtags fnodes mappings .hgtags fnodes cache entries can be expensive to compute, especially if there are hundreds of even thousands of them. This patch implements support for receiving a bundle2 part that contains a mapping of changeset to .hgtags fnodes. An upcoming patch will teach the server to send this part, allowing clients to bypass having to redundantly compute these values. A number of tests changed due to the client advertising the "hgtagsfnodes" capability.

changegroup: rename _computeoutgoing to computeoutgoing We're going to use this function from another module in an upcoming patch. Drop the _ prefix to mark it as non-private.

test-treemanifest: add globs for Windows

test-import: sync with 6084926366b9 for platforms without execbit

hgwebdir: avoid redundant repo and directory entries when 'web.name' is set Previously, when 'web.name' was set on a subrepo parent and 'web.collapse=True', the parent repo would show in the list with the configured 'web.name', and a directory with the parent repo's filesystem name (with a trailing slash) would also appear. The subrepo(s) would unexpectedly be excluded from the list of repositories. Clicking the directory entry would go right to the repo page. Now both the parent and the subrepos show up, without the additional directory entry. The configured hgweb paths used '**' for finding the repos in this scenario. A couple of notes about the tests: - The area where the subrepo was added has a comment that it tests subrepos, though none previously existed there. One now does. - The 'web.descend' option is required for collapse to work. I'm not sure what the previous expectations were for the test. Nothing changed with it set, prior to adding the code in this patch. It is however required for this test. - The only output changes are for the hyperlinks, obviously because of the 'web.name' parameter. - Without this code change, there would be an additional diff: --- /usr/local/mercurial/tests/test-hgwebdir.t +++ /usr/local/mercurial/tests/test-hgwebdir.t.err @@ -951,7 +951,7 @@ /rcoll/notrepo/e/ /rcoll/notrepo/e/e2/ /rcoll/notrepo/f/ - /rcoll/notrepo/f/f2/ + /rcoll/notrepo/f/ Test repositories inside intermediate directories I'm not sure why the fancy name doesn't come out, but it is enough to demonstrate that the parent is not listed redundantly, and the subrepo isn't skipped.