Performance of bzr update for lightweight checkout

[Ulrich Mueller]

>>>>> On Fri, 04 Feb 2011, Aaron Bentley wrote:

> On 11-02-04 11:57 AM, Ulrich Mueller wrote:
>> In Gentoo, we have a live ebuild for GNU Emacs that will access their
>> repository at savannah.gnu.org. The initial checkout is done with
>> "bzr checkout --lightweight" because we don't need any history.

>> During the last month I have noticed that on several of my updates
>> huge amounts of data, about 700 MB, were transferred.
>> Am I doing anything wrong?

> Lightweight checkouts are meant for use in high-bandwidth, low-latency
> environments, such as LANs or local disk.  It sounds like you should be
> using heavyweight checkouts or branches instead.

We'd love to do so, but the time needed for the initial (heavyweight)
checkout seems prohibitive:

   $ date; bzr checkout bzr://bzr.savannah.gnu.org/emacs/trunk/ emacs-test; date
   Fri Feb  4 18:21:11 CET 2011
   Fri Feb  4 19:58:06 CET 2011

That's 97 minutes (and I did this test at work, with a fast network
connection).

> In order to perform an update, you need history.  Most of the data you
> see being transferred will be history data.

Sorry, but I don't understand. It shouldn't need the full history, but
only the history leading from the old to the new revision? And 700 MB
for the update are even more than the amount of data transferred for
an initial heavyweight checkout, which is around 550 MB.

Ulrich