Actually, I'm not sure that the problem is exceptionally kernel-dependent, the package "linux" was submitted to ubuntu-bug command line, since a package name is a mandatory parameter. The problem itself is, that when starting to copy any data to a USB connected media, the copying progress is fast only for a few seconds; after 10-20 seconds and a couple hundred megabytes copied, the progress speed is greatly reduced, so that a file about 1 Gb in size can be copied for about 15 minutes to complete. Trying to use dd command with those external devices, returns the write speed at their proper rates, such as ~20Mbps for USB Flash drives, for example, but once a REAL file is started copying, the speed runs down after several seconds, as described above. I tried to solve the problem installing any new kernel versions, assuming it could be a kind of result of the notorious bug #12309, but, installing the 3.0.x-lts-oneiric-backport kernel from PPA didn't help any way; but, when having installed mainline 3.4.x-precise, the problem some way reduced, the speed decrease and the overall data copying time became less significant.
I am using AMD64 versions of Ubuntu on a system based upon NVIDIA NFORCE 4 Ultra chipset (ASUS A8N-E Socket 939 mainboard), AMD Athlon X2 3800+ CPU, 2x512Mb or 4x512Mb Transcend DDR400 (PC3200) memory modules in dual channel, 128-bit mode (other memory configurations and video card / other peripherals were also used time to time, nothing changed).
ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: linux-image-3.0.0-20-generic 3.0.0-20.34~lucid1
ProcVersionSignature: Ubuntu 3.0.0-20.34~lucid1-generic 3.0.30
Uname: Linux 3.0.0-20-generic x86_64
Architecture: amd64
Date: Sun May 27 03:03:06 2012
InstallationMedia: Ubuntu 10.04 "Lucid Lynx" - Release Candidate amd64 (20100419)
ProcEnviron:
LANGUAGE=ru_UA:en
LANG=ru_UA.utf8
SHELL=/bin/bash
SourcePackage: linux-lts-backport-oneiric
P.S. Speaking about the 12309 bug, I mean not what was parsed by the launchpad engine in my report, but the well-known overall system performance problem when copying data to external devices, related to kernel task scheduler issues.