Mercurial bug cloning xen repo

[Matt Mackall]

On Tue, Sep 20, 2005 at 10:04:50AM -0700, Matt Mackall wrote:
> On Tue, Sep 20, 2005 at 01:03:13PM +0100, Mike Wray wrote:
> > I got the following error when trying to clone the xen unstable repo.
> > This was using mercurial from a fresh pull today (see below for info)
> > and python 2.4.1.
> 
> Hmm, I couldn't reproduce this.
> 
> > mjw at wray-m-3 1022> hg clone http://xenbits.xensource.com/xen-unstable.hg
> > requesting all changes
> > adding changesets
> > adding manifests
> > adding file changes
> > added 6917 changesets with 0 changes to 0 files
>                              ^^^^^^^^^^^^^^^^^^^^
> Something bad happened there. I got:
> 
> requesting all changes
> adding changesets
> adding manifests
> adding file changes
> added 6964 changesets with 69703 changes to 7199 files

Ok, running on the theory that the http connection is closing
prematurely, I did the following:

$ hg bundle ../xenbundle.hg ../empty
searching for changes
$ cd ..
$ dd if=xenbundle.hg of=xentrunc.hg bs=1024 count=2000
$ hg init xentrunc
$ cd xentrunc/
$ hg unbundle ../xentrunc.hg
adding changesets
adding manifests
adding file changes
added 6964 changesets with 0 changes to 0 files
                           ^^^^^^^^^^^^^^^^^^^^
 so we've truncated past the end of the changesets but before the
 beginning of the file deltas

$ dd if=xenbundle.hg of=xentrunc.hg bs=1024 count=1024
$ rm -rf xentrunc
$ mkdir xentrunc; cd xentrunc
$ hg init
$ hg unbundle ../xentrunc.hg
adding changesets
adding manifests
adding file changes
added 6672 changesets with 0 changes to 0 files
      ^^^^

 and now we've not got all the changesets.

The only difference between the bundle protocol and the wire protocol
is the compression: the wire protocol uses zlib to reduce server load,
while bundle uses bzip2. So I suspect what's happening is that the Xen
webserver is cutting off connections that hit 1MB of data transfer in
some situations. The fact that it's repeatable suggests a hard limit.
 
-- 
Mathematics is the supreme nostalgia of our time.