Hey Michael, sorry I've not been participating recently.
I've had a good look at Aptdaemon and touched on the Python APT
bindings.
This is what I envision:
A transaction's download and install parts are separated.
== Install ==
The install part should be like apt-get's '--no-download' option, so
'_apply_changes' should never download files. No lock should be waiting
for a download; this is wasting time. Only
installs/removes/upgrades/triggers/etc should be holding a lock; the
things that actually need it.
When taking the next transaction in the queue in the function
'_on_transaction_done', instead of:
next_trans = self._queue.popleft()
next_trans should be the next transaction /that has nothing to download/.
== Download ==
apt-get's '--print-uris' option outputs lines like this:
'http://gb.archive.ubuntu.com/ubuntu/pool/universe/g/gnash/gnash_0.8.9-1ubuntu1_i386.deb'
gnash_0.8.9-1ubuntu1_i386.deb 197240
MD5Sum:32996ac2d709e1c6e0b65a90272202bb
Of course all of this information can be represented in the form of a
magnet URI, something like this:
magnet:?as=http%3A//gb.archive.ubuntu.com/ubuntu/pool/universe/g/gnash/gnash_0.8.9-1ubuntu1_i386.deb&dn=gnash_0.8.9-1ubuntu1_i386.deb&xl=197240&xt=urn:md5:32996ac2d709e1c6e0b65a90272202bb
If the apt repo could also supply the BTIH, then the whole thing becomes
very easy. A 'xt=urn:btih:' parameter can be added to the magnet which
will be sent via RPC to Aria2 in daemon mode or deluge's server part.
This approach could also allow load balancing of mirrors by specifying
multiple Acceptable Source ('as') params to the magnet, and would make
it trivial to obtain packages from other machines on the LAN making
downloads upto 2 orders of magnitude faster out-of-the-box.
I prefer the idea of having only one download utility on a machine (or
even a LAN), this way downloads can be reordered or paused by any RPC
client.
When each file completes it is placed in /var/cache/apt/archives/ as
usual, and of course when all files for a transaction complete, that
transaction can be applied.
So how is this sounding? Personally, I can't wait to get this working.
--
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/830492
Title:
Downloads should not lock apt
To manage notifications about this bug go to:
https://bugs.launchpad.net/apt/+bug/830492/+subscriptions
--
ubuntu-bugs mailing list
ubuntu-bugs@lists.ubuntu.com
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
