[opensuse-factory] I/O Performance much lower with new 3.17 kernel?!?
Hi there, this is just a heads-up message to check if other people made similar observations. Yesterday I've updated my systems ("zypper dup") from the former Factory release (sometime in October) to version "20141029 (Harlequin)". Apart from the trouble with VMware's modules everything appears as it did before. Now that I'm actually using this system, I realized that fetching e-mails from my local mailserver (postfix + dovecot22) using the fetchmail program is awfully slow. Before, a whole bunch of messages arrived on my workstation without any significant delay; now, running the same on kernel version 3.17.1-1.2.g5c4d099 looks like one e-mail per second. I've seen similar poor performance of fetchmail with IPv6 enabled (but not actually used) before, so I disabled IPv6 both on the server as well as on the client side, but didn't get any change or even improvement. I have now installed kernel version 3.16.7-1.gdfcb69e-desktop (from Kernel:/openSUSE-13.2/standard) and performance is back to normal. I don't know if this is a networking or a file system issue, but thought I'm going to report it here to check other people's opinions and/or experience. Here are some details about my system (server and client are identically configured): CPU: Intel(R) Core(TM) i7-3770 CPU @ 3.40GHz RAM: 32 GiB Swap: 1 GiB (completely unused, just configured for safety) Root: 32 GiB btrfs on SSD Boot: 512 MiB ext2 on SSD Home: 1.9 TiB xfs on soft-raid10 with 4 hard disks Net: Realtek RTL8111/8168 PCI Express Gigabit Ethernet controller + soft-bridging on top for virtualisation Your feedback is highly appreciated! TIA, cheers. l8er manfred
On Monday 2014-11-03 15:27, Manfred Hollstein wrote:
Before, a whole bunch of messages arrived on my workstation without any significant delay; now, running the same on kernel version 3.17.1-1.2.g5c4d099 looks like one e-mail per second. [...] I have now installed kernel version 3.16.7-1.gdfcb69e-desktop (from Kernel:/openSUSE-13.2/standard) and performance is back to normal. I don't know if this is a networking or a file system issue
That is somewhat easy to figure out - download files into tmpfs (e.g. /dev/shm) and measure the two kernels. -- To unsubscribe, e-mail: opensuse-factory+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-factory+owner@opensuse.org
On Fri, 07 Nov 2014, 12:15:15 +0100, Jan Engelhardt wrote:
On Monday 2014-11-03 15:27, Manfred Hollstein wrote:
Before, a whole bunch of messages arrived on my workstation without any significant delay; now, running the same on kernel version 3.17.1-1.2.g5c4d099 looks like one e-mail per second. [...] I have now installed kernel version 3.16.7-1.gdfcb69e-desktop (from Kernel:/openSUSE-13.2/standard) and performance is back to normal. I don't know if this is a networking or a file system issue
That is somewhat easy to figure out - download files into tmpfs (e.g. /dev/shm) and measure the two kernels.
yeah, in the meantime I almost narrowed it down to a fetchmail-only problem. Everything else (local file system access, NFS access) appears to perform at very similar numbers, it's just fetchmail that is annoyingly slow... Cheers. l8er manfred
Hi there, On Fri, 07 Nov 2014, 12:57:43 +0100, Manfred Hollstein wrote:
On Fri, 07 Nov 2014, 12:15:15 +0100, Jan Engelhardt wrote:
On Monday 2014-11-03 15:27, Manfred Hollstein wrote:
Before, a whole bunch of messages arrived on my workstation without any significant delay; now, running the same on kernel version 3.17.1-1.2.g5c4d099 looks like one e-mail per second. [...] I have now installed kernel version 3.16.7-1.gdfcb69e-desktop (from Kernel:/openSUSE-13.2/standard) and performance is back to normal. I don't know if this is a networking or a file system issue
That is somewhat easy to figure out - download files into tmpfs (e.g. /dev/shm) and measure the two kernels.
yeah, in the meantime I almost narrowed it down to a fetchmail-only problem. Everything else (local file system access, NFS access) appears to perform at very similar numbers, it's just fetchmail that is annoyingly slow...
I just tried the new 3.18.0-2.g2b473fc-desktop kernel from Kernel:HEAD and the performance problems are gone. It looks like it's only a 3.17 problem. I'll put it into bugzilla. Cheers. l8er manfred
participants (2)
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Jan Engelhardt -
Manfred Hollstein