-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 On 08/10/14 17:36, Steve Langasek wrote: > Hi Jonathan, > > On Wed, Oct 08, 2014 at 03:56:42PM +0100, Jonathan Riddell wrote: >> Me and Rohan would like a second opinion on bug 1378789 >> [SRU] Set the default IO scheduler to CFQ in Kubuntu Trusty >> https://launchpad.net/bugs/1378789 > >> The kernel team have changed the scheduler away from upstream Linux >> defaults to deadlock which causes our desktop indexing programme Baloo >> to run very slow and take up lots of resources because it doesn't >> implement ionice suport. We'd like to update kubuntu-settings with a >> udev rule to change back to CFQ. > >> We've changed this in utopic. There's minimal chance of regressions, >> it's an upstream default recommended by Linux and Baloo. We're >> getting quite a few reports of people saying their system is sluggish >> and the baloo upstream author is most grumpy. > >> Scott would rather wait until after utopic is out where it would get >> more testing, but I doubt there will be much that most users can say >> beyond "it's not horribly slow". > > I don't think it's at all appropriate for a desktop environment to install a > udev rule which changes the kernel scheduler. That's a severe layering > violation, and it means that anyone who installs kubuntu-desktop on an > existing system will significantly change the performance characteristics of > that system. > > I also think it's categorically wrong to say that there's minimal chance of > regression. These schedulers have pretty fundamentally different > characteristics, and where CFQ behaves pathologically for one process (the > indexer), deadline will behave pathologically for others. > > I don't think it's at all acceptable to work around a kernel bug in a > kubuntu-settings SRU. The right fix is to resolve this in the kernel > package instead. (Bug #1310402) Cc:ing the kernel team. > > Also, what exactly do you mean when you say baloo doesn't "implement ionice > support"? The 'ionice' tool is part of the base system (util-linux). It > would be a simple matter of packaging to always run baloo under ionice.
Linux supports I/O scheduling priorities since 2.6.13 just with the CFQ io scheduler. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBCAAGBQJUNWmHAAoJEGjCh9/GqAImE1oP/0cRps85qcUvLxtO84smMTzp HHw0HNu21Wot20wC4PgmI4+XHWpEifbjYMnLFU99DUGvSHeieZFy6nq0BN/30gKg FBP7aif0P9hCeTrTBCN1YG18PsY71dhc9QatWz3xjhQc/VFVU9I8F4k6i4Sk1sD2 zBRPeI5m4q66nmipAe1/+5FEJbxQJV7+3xYOp8QQPwpaJKHu29Zp6m/GPvxM10kS 1DhYy6RI/1LiC8L867cn6IN1eC30LaECKwPr8kI9/lfp4M0BdYiQOtyLDlchLdjS ZH8XaPiV2SMEsQCNlu4/8CPU2yoxKnVR8LZInJPVljctYvZqB2+EK97S9x6mAwXk 8DjHlvjy0O57V5T+5q0cbOfG6FQ8iExBNkO9waY27iRcneLvhQyEnz4boNKgSG2B JOv+DP64wiSHnKV0Q2pq7zBzlNFvaVj8wRYmGM9NTTjuCL1IocVt1j5HgGNWJawb FTKWVWqwzlANMhZLMcX8sfgVoZoD4t7fhe7fhLbkoCp0Bvto4EPmXRI/gOCRE19R qQAdrVVXd1X3oDMR7dZFEYEZ+JELJKgsg6RgQkFeRIoc0TbhY9EMxQhHG6kzQJvM WfeVAXsGo6e9IAAMCsVT0vc8jbuyS6ioz8meyyGRXvtdbF/wFAKf/Aacdo3upq6H PaeN3Z7C9Edseb50itoU =yBjp -----END PGP SIGNATURE----- -- kubuntu-devel mailing list kubuntu-devel@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/kubuntu-devel
