[10:12] hey ho [10:13] cking, you did some testing for us, on cfq/deadline etc, as we were considering flipping back to cfq "because clearly it is better" ... and it wasn't [10:13] cking, shadeslayer is asking to switch to cfq ... [10:13] apw, as per usual, it depends on the usecase [10:14] fwiw userland stuff depends on CFQ https://bugs.launchpad.net/bugs/1310402 [10:14] Ubuntu bug 1310402 in linux "Userland depends on ionice idle but default scheduler is "deadline". " [Wishlist,Triaged] [10:14] Ubuntu bug 1310402 in linux (Ubuntu) "Userland depends on ionice idle but default scheduler is "deadline". " [Wishlist,Triaged] [10:14] shadeslayer, well you can simply change it via sysfs [10:14] apw: I'm not arguing about that [10:14] it's just that it seems like a runtime dep [10:15] but as i recall the analysis we switched to deadline, because we saw visible delayes in desktop from cfq [10:15] I see, atleast for Kubuntu we wanted to switch to CFQ because the file indexer was trashing the HDD since io niceness was not available on deadline [10:16] so I kind of did this https://launchpad.net/ubuntu/+source/kubuntu-settings/1:14.10ubuntu3 [10:16] which seems reasonable [10:16] the main problem is that whatever one choses there will be cases where one ioscheduler is better than the other [10:17] I'm not arguing against that :D [10:17] i am not actually sure what you are arguing [10:17] All I'm saying is that some userland stuff depends on CFQ [10:17] and I was wondering if there was testing done to see if we can change to CFQ [10:18] and wanted to look at testing data [10:18] because I want to see cases where deadline is better on the desktop [10:18] and see how kubuntu would be affected [10:18] there has been testing done over a wide range of kernels and I doubt we will switch for this release [10:19] yep, that's reasonable since we're past FF [10:19] but data :( [10:19] where do I find the data :( [10:20] shadeslayer, it's currently not published because I'm still working on a fully automated test rig [10:20] and with so many schedulers, file system times, media and kernels it's taking a while to gather a full set of data across releases + kernels [10:21] okay, do you have a document that has testing parameters and such? [10:21] cking: I assume the tests for the desktop are only run for Unity? [10:22] shadeslayer, nope, it's all command line driven with 20 or so fio tests [10:22] okay [10:22] http://kernel.ubuntu.com/git?p=cking/fs-test-proto.git;a=summary [10:22] and it's PROTO type code [10:22] ack [10:23] i.e. it's bound to have bugs and it's still work in progress [10:25] shadeslayer, perhaps there is something to be said to getting your "select scheduler" job into something common to all servers etc to have different defaults [10:25] shadeslayer, when I get some free time I'll try and write a fio test that reproduces that issue in that bug report [10:26] apw: possibly [10:27] it almost wants to be a kernel thing, though we don't really have "one package" due to the "multiple kernels installed" .... hmmm [10:27] I just picked it up from the debian docs on udev rules, so I'm not really in the best position to write a more complex rule [10:30] it would be nice if one had /etc/default/linux which let us change "things" which are kernel side, hmmm [10:35] apw, yeah, like defaults for types of usecases, e.g. webserver, database, mailserver, desktop HDD,desktop SSD, etc [10:51] cking: apw btw do these tests also test things like apps contending for disk reads/writes ? [10:51] because for the desktop that would be the most important thing [10:51] shadeslayer, some of my fio test do simulate multiple reader writers in different i/o patterns === zequence_ is now known as zequence === willcooke is now known as willcooke|meetin === dannf` is now known as dannf === alai` is now known as alai === willcooke|meetin is now known as willcooke === cmagina_ is now known as cmagina_airport === cmagina_airport is now known as cmagina_mobile === jsalisbury changed the topic of #ubuntu-kernel to: Home: https://wiki.ubuntu.com/Kernel/ || Ubuntu Kernel Team Meeting - Tues September 9th, 2014 - 17:00 UTC || If you have a question just ask, and do wait around for an answer! If the question is should I file a bug for something, likely you can assume yes. === willcooke_ is now known as willcooke === utlemming is now known as utlemming_away [20:22] !ops [20:22] Help! lamont, zul, T-Bone, mdz, or jdub [20:22] Help! lamont, zul, T-Bone, mdz, or jdub [20:22] !ops [20:22] Help! lamont, zul, T-Bone, mdz, or jdub [20:22] Help! lamont, zul, T-Bone, mdz, or jdub [21:12] dannf, we've not turned the crank on a new trusty yet. i expect rtg will get those ahci xgene patches sorted. don't know what happened there. [21:12] bjf: ack, thx