changeset 27738:a0e783d26e81

exchange: make clone bundles non-experimental and enabled by default The clone bundles feature was introduced in Mercurial 3.6 behind an experimental and disabled by default flag. The feature has been enabled on hg.mozilla.org for a few months and has served many terabytes of clones. Users have been encouraged to use the feature and reception has been very positive (mainly due to faster clones as a result of connecting to a CDN). I have heard no feedback about changing the feature other than inquiries about when it will be enabled by default. So, I think the feature is ready to be enabled by default. This patch renames experimental.clonebundles to ui.clonebundles, documents the option, and enables it by default. References to the experimental state of clone bundles have been removed. The remaining config option docs in clonebundles.py have been removed because they are redudant with `hg help config`. There are some oddities with behavior of clone bundles. Because clones with clone bundles are effectively 2 `hg pull` operations, there may be 2 transactions. This could result in hooks running twice. If the subsequent pull is aborted, it could result in partial rollback and an incomplete clone. This behavior is a bit wonky and should probably be documented. If this patch is accepted, I'll send a follow-up to document it. I don't think this behavior should prevent the feature being enabled by default. Reworking the clone mechanism to support interrupted or multi-part clones feels like a major new feature and something that when implemented can change the hook and rollback semantics of clone bundles. Besides, partial clone is better than full rollback and hooks running on initial clone are likely rare, so I think the impact is minimal.
author Gregory Szorc <gregory.szorc@gmail.com>
date Fri, 08 Jan 2016 10:58:04 -0800
parents 482eb357fe98
children d6d3cf5fda6f
files hgext/clonebundles.py mercurial/exchange.py mercurial/help/config.txt tests/test-clonebundles.t tests/test-help.t
diffstat 5 files changed, 18 insertions(+), 40 deletions(-) [+]
line wrap: on
line diff
--- a/hgext/clonebundles.py	Fri Jan 08 10:57:01 2016 -0800
+++ b/hgext/clonebundles.py	Fri Jan 08 10:58:04 2016 -0800
@@ -1,7 +1,7 @@
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
-"""advertise pre-generated bundles to seed clones (experimental)
+"""advertise pre-generated bundles to seed clones
 
 "clonebundles" is a server-side extension used to advertise the existence
 of pre-generated, externally hosted bundle files to clients that are
@@ -160,16 +160,6 @@
 occurs. So server operators should prepare for some people to follow these
 instructions when a failure occurs, thus driving more load to the original
 Mercurial server when the bundle hosting service fails.
-
-The following config options influence the behavior of the clone bundles
-feature:
-
-ui.clonebundlefallback
-   Whether to automatically fall back to a traditional clone in case of
-   clone bundles failure. Defaults to false for reasons described above.
-
-experimental.clonebundles
-   Whether the clone bundles feature is enabled on clients. Defaults to true.
 """
 
 from mercurial import (
--- a/mercurial/exchange.py	Fri Jan 08 10:57:01 2016 -0800
+++ b/mercurial/exchange.py	Fri Jan 08 10:58:04 2016 -0800
@@ -1677,7 +1677,7 @@
     repo = pullop.repo
     remote = pullop.remote
 
-    if not repo.ui.configbool('experimental', 'clonebundles', False):
+    if not repo.ui.configbool('ui', 'clonebundles', True):
         return
 
     # Only run if local repo is empty.
@@ -1733,7 +1733,7 @@
                           hint=_('if this error persists, consider contacting '
                                  'the server operator or disable clone '
                                  'bundles via '
-                                 '"--config experimental.clonebundles=false"'))
+                                 '"--config ui.clonebundles=false"'))
 
 def parseclonebundlesmanifest(repo, s):
     """Parses the raw text of a clone bundles manifest.
--- a/mercurial/help/config.txt	Fri Jan 08 10:57:01 2016 -0800
+++ b/mercurial/help/config.txt	Fri Jan 08 10:58:04 2016 -0800
@@ -1487,6 +1487,16 @@
     default ``USER@HOST`` is used instead.
     (default: False)
 
+``clonebundles``
+    Whether the "clone bundles" feature is enabled.
+
+    When enabled, :hg:`clone` may download and apply a server-advertised
+    bundle file from a URL instead of using the normal exchange mechanism.
+
+    This can likely result in faster and more reliable clones.
+
+    (default: True)
+
 ``clonebundlefallback``
     Whether failure to apply an advertised "clone bundle" from a server
     should result in fallback to a regular clone.
--- a/tests/test-clonebundles.t	Fri Jan 08 10:57:01 2016 -0800
+++ b/tests/test-clonebundles.t	Fri Jan 08 10:58:04 2016 -0800
@@ -20,27 +20,6 @@
   $ cat hg.pid >> $DAEMON_PIDS
   $ cd ..
 
-Feature disabled by default
-(client should not request manifest)
-
-  $ hg clone -U http://localhost:$HGPORT feature-disabled
-  requesting all changes
-  adding changesets
-  adding manifests
-  adding file changes
-  added 2 changesets with 2 changes to 2 files
-
-  $ cat server/access.log
-  * - - [*] "GET /?cmd=capabilities HTTP/1.1" 200 - (glob)
-  * - - [*] "GET /?cmd=batch HTTP/1.1" 200 - x-hgarg-1:cmds=heads+%3Bknown+nodes%3D (glob)
-  * - - [*] "GET /?cmd=getbundle HTTP/1.1" 200 - x-hgarg-1:bundlecaps=HG20%2Cbundle2%3DHG20%250Achangegroup%253D01%252C02%252C03%250Adigests%253Dmd5%252Csha1%252Csha512%250Aerror%253Dabort%252Cunsupportedcontent%252Cpushraced%252Cpushkey%250Ahgtagsfnodes%250Alistkeys%250Apushkey%250Aremote-changegroup%253Dhttp%252Chttps&cg=1&common=0000000000000000000000000000000000000000&heads=aaff8d2ffbbf07a46dd1f05d8ae7877e3f56e2a2&listkeys=phase%2Cbookmarks (glob)
-  * - - [*] "GET /?cmd=listkeys HTTP/1.1" 200 - x-hgarg-1:namespace=phases (glob)
-
-  $ cat >> $HGRCPATH << EOF
-  > [experimental]
-  > clonebundles = true
-  > EOF
-
 Missing manifest should not result in server lookup
 
   $ hg --verbose clone -U http://localhost:$HGPORT no-manifest
@@ -50,7 +29,7 @@
   adding file changes
   added 2 changesets with 2 changes to 2 files
 
-  $ tail -4 server/access.log
+  $ cat server/access.log
   * - - [*] "GET /?cmd=capabilities HTTP/1.1" 200 - (glob)
   * - - [*] "GET /?cmd=batch HTTP/1.1" 200 - x-hgarg-1:cmds=heads+%3Bknown+nodes%3D (glob)
   * - - [*] "GET /?cmd=getbundle HTTP/1.1" 200 - x-hgarg-1:bundlecaps=HG20%2Cbundle2%3DHG20%250Achangegroup%253D01%252C02%252C03%250Adigests%253Dmd5%252Csha1%252Csha512%250Aerror%253Dabort%252Cunsupportedcontent%252Cpushraced%252Cpushkey%250Ahgtagsfnodes%250Alistkeys%250Apushkey%250Aremote-changegroup%253Dhttp%252Chttps&cg=1&common=0000000000000000000000000000000000000000&heads=aaff8d2ffbbf07a46dd1f05d8ae7877e3f56e2a2&listkeys=phase%2Cbookmarks (glob)
@@ -75,7 +54,7 @@
   applying clone bundle from http://does.not.exist/bundle.hg
   error fetching bundle: (.* not known|getaddrinfo failed) (re)
   abort: error applying bundle
-  (if this error persists, consider contacting the server operator or disable clone bundles via "--config experimental.clonebundles=false")
+  (if this error persists, consider contacting the server operator or disable clone bundles via "--config ui.clonebundles=false")
   [255]
 
 Server is not running aborts
@@ -85,7 +64,7 @@
   applying clone bundle from http://localhost:$HGPORT1/bundle.hg
   error fetching bundle: * refused* (glob)
   abort: error applying bundle
-  (if this error persists, consider contacting the server operator or disable clone bundles via "--config experimental.clonebundles=false")
+  (if this error persists, consider contacting the server operator or disable clone bundles via "--config ui.clonebundles=false")
   [255]
 
 Server returns 404
@@ -96,7 +75,7 @@
   applying clone bundle from http://localhost:$HGPORT1/bundle.hg
   HTTP error fetching bundle: HTTP Error 404: File not found
   abort: error applying bundle
-  (if this error persists, consider contacting the server operator or disable clone bundles via "--config experimental.clonebundles=false")
+  (if this error persists, consider contacting the server operator or disable clone bundles via "--config ui.clonebundles=false")
   [255]
 
 We can override failure to fall back to regular clone
--- a/tests/test-help.t	Fri Jan 08 10:57:01 2016 -0800
+++ b/tests/test-help.t	Fri Jan 08 10:58:04 2016 -0800
@@ -252,7 +252,6 @@
        censor        erase file content at a given revision
        churn         command to display statistics about repository history
        clonebundles  advertise pre-generated bundles to seed clones
-                     (experimental)
        color         colorize output from some commands
        convert       import revisions from foreign VCS repositories into
                      Mercurial
@@ -1309,7 +1308,7 @@
   
   Extensions:
   
-   clonebundles advertise pre-generated bundles to seed clones (experimental)
+   clonebundles advertise pre-generated bundles to seed clones
    prefixedname matched against word "clone"
    relink       recreates hardlinks between repository clones