Public bug reported: [Impact] Downloading many packages on archive.ubuntu.com or some other mirrors seems to close the connection after every 100 or so packages. APT prior to 1.7.0~rc1 (commit df696650b7a8c58bbd92e0e1619e956f21010a96), treats a connection closure with a 200 response as meaning that the server does not support pipelining, hence disabling it for any further downloads.
With high speed connections at higher latency, this can cause a severe reduction in usable bandwidth. For example, I saw speeds drop from 40 MB/s to 15 MB/s due to this. The fix ensures that we continue pipelining if the previous connection to the server successfully retrieved at least 3 files with pipelining enabled. [Test case] Pick a package that would cause a large number (200/300 packages of packages to be installed). I used plasma-desktop and xubuntu-desktop, for example. Run apt install -d $package. Ensure that after the first 101 packages the progress does not slow down - you should not see a lot "working" in the progress output. The speed should be substantially higher. Requirements: * High speed, medium-high latency connection (e.g. 400 Mbit/s at 30 ms RTT is enough) * Not a terribly slow CPU, as we'd get slowed down by hashing otherwise [Regression potential] This fix is isolated to code enabling/disabling pipelining on subsequent connections. It could cause more pipelining to be tried on servers who are not particularly good at it, but can deal with 3 items correctly. ** Affects: apt (Ubuntu) Importance: Undecided Status: Fix Released ** Affects: apt (Ubuntu Xenial) Importance: Undecided Status: Triaged ** Affects: apt (Ubuntu Bionic) Importance: Undecided Status: Triaged ** Changed in: apt (Ubuntu) Status: New => Fix Released ** Also affects: apt (Ubuntu Bionic) Importance: Undecided Status: New ** Also affects: apt (Ubuntu Xenial) Importance: Undecided Status: New ** Changed in: apt (Ubuntu Xenial) Status: New => Triaged ** Changed in: apt (Ubuntu Bionic) Status: New => Triaged -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1794957 Title: pipelining on archive.u.c aborts after 101 packages To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/apt/+bug/1794957/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs