Hi all, After compiling kernels for a while I found out why the Fedora's kernel works for me: it is built without PAE support. I've bisected Ubuntu' and Fedora's .config files and it turnes out that CONFIG_HIGHMEM4G=y "fixes" my issue ;) .
After that I rebooted my machine with default Ubuntu kernel (PAE) and 16Gb RAM, not 32GB, and it also "fixed" my issue ;) After that I built a kernel with PAE, 32GB but with CONFIG_VMSPLIT_1G=y , and again, it really fixed my issue (but it is incompatible with binary drivers, see documentation; and my fglrx didn't work). To wit: Linux kernel doesn't work well with 32bit, PAE and >=32 Gb RAM. (I even saw such statemets somewhere on the Net.) Am I right? If so, I think Ubuntu documentation should state it explicitly. ** Summary changed: - IO limit 1.2 MB/s for 32bit ubuntu (ACPI issues) + IO limit 1.2 MB/s for 32bit ubuntu (PAE, 32 Gb RAM) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1264707 Title: IO limit 1.2 MB/s for 32bit ubuntu (PAE, 32 Gb RAM) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1264707/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
