[arch-dev-public] [RFC] Moving repos to nymeria

Tom Gundersen teg at jklm.no
Sun Sep 16 05:21:16 EDT 2012

> Am 16.09.2012 08:34, schrieb Jan Steffens:
>> I want avoid anything that requires me to upload the DB from my computer.


>> That would be over 7MB I would have to download and upload

Would we really need to sign the full 7MB database? Could we not come
up with something more minimal to sign that would still be sufficient?
Alternatively, we need to get Jan a better connection :)

On Sun, Sep 16, 2012 at 9:47 AM, Pierre Schmitz <pierre at archlinux.de> wrote:
> Exactly, this is not an option. Also remember that we need to lock the
> db during that time so nobody else can modify it. Transactions are also
> way harder to handle; what if the upload fails etc...

We don't need to lock the database for the duration of the
download/sign/upload. We could simply:

 * check the timestamp of the old database
 * download the database
 * check the old signature
 * update the database and sign the new version
 * upload the database
 * lock the database on the server
 * check if the timestamp has changed
   * if yes, release the lock and start from scratch
   * if no, overwrite it with your new version and release the lock

This means that you might need to retry once or twice if more than one
person is updating the database, so it does not scale that well.
However, we are not that many people and we don't update the database
that often, so the chance of actually getting a conflict is low (and
the additional cost is not that high either).


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