Did anyone try koala alpha 3? I did and have some interesting behavior.
My machine (a intel motherboard with a G33 chipset) and Core 2 Duo E6600 processor. It has 2 SATA drives under AHCI and I use a 64bit kernel. I can easily reproduce the problem using the fsync-tester program that you can get in the kernel bug #12309 (http://bugzilla.kernel.org/show_bug.cgi?id=12309). All I need to do is to run the program with a dd that creates very large file with the command line: dd if=/dev/zero of=./bigfile bs=1M count=15000 & ./fsync-tester In jaunty (ext3) the desktop becomes unresponsive right away. The times given by fsync-tester look like: fsync time: 0.5422 fsync time: 6.3691 fsync time: 8.5983 fsync time: 0.7820 fsync time: 0.7695 fsync time: 4.6577 fsync time: 5.6024 fsync time: 9.4238 fsync time: 10.8609 I tried some variations of koala. Here are my findings: 1) 64bit Koala in default configuration (ext4). The desktop is more responsive, but not really good yet. The fsync- tester gives: fsync time: 0.1351 fsync time: 0.9104 fsync time: 9.1311 fsync time: 1.9133 fsync time: 11.9529 fsync time: 1.6751 fsync time: 2.7171 fsync time: 8.4801 So the better responsiveness is not related to the fsync times, probably it is related to other changes in the kernel. There is no clear change if I go from turn AHCI off in the bios. 2) If I change the journal mode to writeback, the fsync times improve a lot (and the responsiveness improve): fsync time: 0.0781 fsync time: 0.0581 fsync time: 1.7040 fsync time: 1.4743 fsync time: 1.5957 fsync time: 1.7751 fsync time: 1.9164 fsync time: 1.4886 fsync time: 1.3991 fsync time: 1.8332 3) If on the other hand, I use a i386 kernel with the default ordered mode the times are also much better (as good as writeback + amd64): fsync time: 0.0677 fsync time: 3.8825 fsync time: 1.4467 fsync time: 2.7759 fsync time: 1.5819 fsync time: 3.2423 fsync time: 3.4318 fsync time: 1.5432 fsync time: 1.3225 4) i386 + writeback gets a little better: fsync time: 0.0946 fsync time: 1.3528 fsync time: 1.4029 fsync time: 1.3787 fsync time: 1.0880 fsync time: 1.2656 fsync time: 0.9047 fsync time: 0.8842 fsync time: 0.8008 fsync time: 1.4933 fsync time: 1.3645 (There are know 3s delays as above) 5) Now comes the interesting surprise. If I install amd64 koala using ext3 with its default mode (which I think is writeback, but I am not sure). I get very good responsiveness and times: fsync time: 0.0329 fsync time: 0.0156 fsync time: 0.2369 fsync time: 0.1274 fsync time: 0.2285 fsync time: 0.2196 fsync time: 0.2563 fsync time: 0.2147 fsync time: 0.2968 fsync time: 0.2602 fsync time: 0.1131 fsync time: 0.2348 I didn't try i386+ext3. I ran out of time and patience :-) So, in my computer the problem seems to be related with many factors: amd64 X i386, writeback X ordered mode, and ext4 X ext3. It would be very interesting if anyone can reproduce my little experiment. And remember, if you are annoyed by this bug you may want to stick with ext3 in koala for now. -- Heavy Disk I/O harms desktop responsiveness https://bugs.launchpad.net/bugs/131094 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
