On 25/07/18 12:34, George Dunlap wrote: > On Wed, Jul 25, 2018 at 12:30 PM, Andrew Cooper > <andrew.coop...@citrix.com> wrote: >> On 25/07/18 12:24, George Dunlap wrote: >>> On Wed, Jul 25, 2018 at 10:22 AM, Juergen Gross <jgr...@suse.com> wrote: >>>> On 25/07/18 10:19, Andrew Cooper wrote: >>>>> On 25/07/2018 09:15, Julien Grall wrote: >>>>>> Hi Juergen, >>>>>> >>>>>> On 25/07/18 08:19, Juergen Gross wrote: >>>>>>> Its time to plan the Xen 4.12 release dates. >>>>>>> >>>>>>> There have been concerns with the schedule of 6 months between releases, >>>>>>> as this scheme is leading to too many supported versions of Xen at a >>>>>>> time. The needed resources to backport bug fixes and security fixes as >>>>>>> well as doing the tests for all those releases are a limiting factor to >>>>>>> push out the current main release as well as point releases on time. >>>>>>> >>>>>>> After some discussions at the Xen developer summit, on xen-devel and >>>>>>> between the committers a slightly longer release cycle of 8 or 9 months >>>>>>> was suggested. >>>>>>> >>>>>>> With 18 months of full support and 36 months of security support the >>>>>>> number of concurrent supported releases will be the same with either 8 >>>>>>> or 9 months release cycles, so I have chosen an 8 month cycle for now. >>>>>>> Having only 3 possible times in the year for a release will make it >>>>>>> easier to avoid major holiday seasons. > >>>>>>> In case there is no objection I'm planning Xen 4.12 with: >>>>>>> >>>>>>> * Last posting date: December 14th, 2018 >>>>>>> * Hard code freeze: January 11th, 2019 >>>>>> In general, you would expect western people to slow down during >>>>>> Christmas period and have to deal with a pile of e-mail just after New >>>>>> Year. So I think, this is not very convenient period for a code freeze. >>>>>> >>>>>> I usually take more holidays around Christmas and New Year. For this >>>>>> year, I will be on holidays from 21st December until the 13th January. >>>>>> This basically means my cut off for Arm patches will be 21st December >>>>>> or potentially few days before to avoid having the likely last minute >>>>>> rush. >>>>> Given that we have decided to switch to a difference cadence, it would >>>>> be prudent to work out when the best alignment of an 8-month cadence >>>>> would be, rather than having it 8 months from now. If that means a >>>>> one-off shorter or longer cycle for 4.12 then so be it. >>>> The general holiday seasons are: >>>> >>>> - Chinese new year (end of January ... mid of February), 2 weeks >>>> - Eastern (end of March ... end of April), only a weak dependency? >>>> - summer (August?), second half of July and first half of September as >>>> a weak dependency >>>> - Christmas (end of December ... start of January), adding one week as >>>> a weak dependency >>>> >>>> We don't like the planned release to be in or just before a holiday >>>> season. The period between last posting date and freeze should last >>>> 2 weeks, the freeze period should last 6 weeks. >>>> >>>> In the diagram below I have used a 'X' for a major holiday season and >>>> a 'x' for a weak dependency. The lines below are possible release date >>>> variants just shifted by a weak each to show all possibilities. >>>> >>>> Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec >>>> Xx.XXXXX...xxxx...........xxXXXXx..............X holidays >>>> ffFFFFFFR.......ffFFFFFFR.......ffFFFFFFR....... >>>> .ffFFFFFFR.......ffFFFFFFR.......ffFFFFFFR...... >>>> ..ffFFFFFFR.......ffFFFFFFR.......ffFFFFFFR..... >>>> ...ffFFFFFFR.......ffFFFFFFR.......ffFFFFFFR.... >>>> ....ffFFFFFFR.......ffFFFFFFR.......ffFFFFFFR... >>>> .....ffFFFFFFR.......ffFFFFFFR.......ffFFFFFFR.. >>>> ......ffFFFFFFR.......ffFFFFFFR.......ffFFFFFFR. >>>> .......ffFFFFFFR.......ffFFFFFFR.......ffFFFFFFR >>>> R.......ffFFFFFFR.......ffFFFFFFR.......ffFFFFFF >>>> FR.......ffFFFFFFR.......ffFFFFFFR.......ffFFFFF >>>> FFR.......ffFFFFFFR.......ffFFFFFFR.......ffFFFF >>>> FFFR.......ffFFFFFFR.......ffFFFFFFR.......ffFFF >>>> FFFFR.......ffFFFFFFR.......ffFFFFFFR.......ffFF >>>> FFFFFR.......ffFFFFFFR.......ffFFFFFFR.......ffF >>>> FFFFFFR.......ffFFFFFFR.......ffFFFFFFR.......ff >>>> fFFFFFFR.......ffFFFFFFR.......ffFFFFFFR.......f >>>> >>>> We can rule out several variants with release dates just before or in a >>>> holiday season: >>>> >>>> Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec >>>> Xx.XXXXX...xxxx...........xxXXXXx..............X holidays >>>> ffFFFFFFR.......ffFFFFFFR.......ffFFFFFFR....... >>>> .ffFFFFFFR.......ffFFFFFFR.......ffFFFFFFR...... >>>> >>>> Best fit seems to be releasing in first half of March/July/November. The >>>> main clash seems to be Chinese new year in the freeze period, but >>>> avoiding that would mean we'd have to either move into Christmas or >>>> Eastern, or to use a schedule with varying periods. >>>> >>>> Please remember that Chinese new year is only 2 weeks long (at varying >>>> dates) so only 2 weeks of the freeze period are hit. Next year the >>>> Chinese new year will be at February 5th. >>>> >>>> For my 4.12 plan I've added some extra weeks between last posting date >>>> and release date to accommodate for the holiday seasons, resulting in >>>> my suggestion. >>> Thanks for the detailed analysis Juregen. This seems good to me. >> I think it is also worth staying that we need to work on reducing the >> length of the hard freeze date, because as is visible from that diagram, >> its basically half the year. > That diagram, however, is basically two years packed into one -- taken > as only a single year it represents a 4-month cycle, not an 8-month > cycle.
Oh - of course. ~Andrew _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
