Rafael, I just successfully merged (strange?) https://github.com/andrijapanic/cloudstack-docs/pull/1 and I can see changes are publicly available on http://docs.cloudstack.apache.org/en/latest/networking/vxlan.html#important-note-on-max-number-of-multicast-groups-and-thus-vxlan-intefaces
Is this normal, that I can merge my own pull request on cloudstack-doc repo ? There is no limitations (I was able to make PR and merge myself) On 21 February 2018 at 00:58, Andrija Panic <andrija.pa...@gmail.com> wrote: > pls merge also https://github.com/apache/cloudstack-docs-admin/pull/48 > > just correct code block syntax (to display code properly) > > On 20 February 2018 at 21:02, Rafael Weingärtner < > rafaelweingart...@gmail.com> wrote: > >> Thanks, we will proceed reviweing >> >> On Tue, Feb 20, 2018 at 3:12 PM, Andrija Panic <andrija.pa...@gmail.com> >> wrote: >> >> > Here it is: >> > >> > https://github.com/apache/cloudstack-docs-admin/pull/47 >> > >> > Added KVM online storage migration (atm only CEPH/NFS to SolidFire, new >> in >> > 4.11 release) >> > Added KVM cache mode setup and limitations. >> > >> > >> > Cheers >> > >> > On 20 February 2018 at 16:49, Rafael Weingärtner < >> > rafaelweingart...@gmail.com> wrote: >> > >> > > If you are willing to write it down, please do so, and open a PR. We >> will >> > > review and merged it afterwards. >> > > >> > > On Tue, Feb 20, 2018 at 12:41 PM, Andrija Panic < >> andrija.pa...@gmail.com >> > > >> > > wrote: >> > > >> > > > I advise (or not...depends on point of view) to stay that way - >> because >> > > > when you activate write-back cache - live migrations will stop, and >> > this >> > > > makes *Enable maintenance mode (put host into maintenance)* >> impossible. >> > > > >> > > > I would perhaps suggest that there is documentation for "advanced >> > users" >> > > or >> > > > similar, that will say "it's possible to enable this and this way >> via >> > DB >> > > > hack, but be warned on live migration consequences etc..." since >> this >> > > will >> > > > render more problems if people start using it. >> > > > >> > > > If you choose to do, let me know, I can write that (documentation) >> > > briefly. >> > > > >> > > > Not to mention it can be unsafe (power failure - less possible I >> guess, >> > > but >> > > > rare kernel panic etc might have it's consequences I assume) >> > > > >> > > > It does indeed increase performance on NFS much, but not >> necessarily on >> > > > CEPH (if you are using lirbd cache on client side as explained >> above) >> > > > >> > > > On 20 February 2018 at 15:48, Rafael Weingärtner < >> > > > rafaelweingart...@gmail.com> wrote: >> > > > >> > > > > Yes. Weird enough, the code is using the value in the database if >> it >> > is >> > > > > provided there, but there is no easy way for users to change that >> > > > > configuration in the database. ¯\_(ツ)_/¯ >> > > > > >> > > > > On Tue, Feb 20, 2018 at 11:45 AM, Andrija Panic < >> > > andrija.pa...@gmail.com >> > > > > >> > > > > wrote: >> > > > > >> > > > > > So it seems that just passing the cachemode value to API is not >> > > there, >> > > > or >> > > > > > somehow messedup, but deployVM process does read DB values from >> > > > > > disk_offering table for sure, and applies it to XML file for >> KVM. >> > > > > > This is above ACS 4.8.x. >> > > > > > >> > > > > > >> > > > > > On 20 February 2018 at 15:44, Andrija Panic < >> > andrija.pa...@gmail.com >> > > > >> > > > > > wrote: >> > > > > > >> > > > > > > I have edited the disk_offering table, in the cache_mode just >> > enter >> > > > > > > "writeback". Stop and start VM, and it will pickup/inherit the >> > > > > cache_mode >> > > > > > > from it's parrent offering >> > > > > > > This also applies to Compute/Service offering, again inside >> > > > > disk_offering >> > > > > > > table - just tested both >> > > > > > > >> > > > > > > i.e. >> > > > > > > >> > > > > > > UPDATE `cloud`.`disk_offering` SET `cache_mode`='writeback' >> WHERE >> > > > > > > `id`=102; # Compute Offering (Service offering) >> > > > > > > UPDATE `cloud`.`disk_offering` SET `cache_mode`='writeback' >> WHERE >> > > > > > > `id`=114; #data disk offering >> > > > > > > >> > > > > > > Before SQL: >> > > > > > > >> > > > > > > root@ix1-c7-4:~# virsh dumpxml i-2-10-VM | grep cache -A2 >> > > > > > > <driver name='qemu' type='qcow2' cache='none'/> >> > > > > > > <source file='/mnt/63a3ae7b-9ea9-3884- >> > > > > a772-1ea939ef6ec3/1b655159- >> > > > > > > ae10-41cf-8987-f1cfb47fe453'/> >> > > > > > > <target dev='vda' bus='virtio'/> >> > > > > > > -- >> > > > > > > <driver name='qemu' type='qcow2' cache='none'/> >> > > > > > > <source file='/mnt/63a3ae7b-9ea9-3884- >> > > > > a772-1ea939ef6ec3/09bdadcb- >> > > > > > > ec6e-4dda-b37b-17b1a749257f'/> >> > > > > > > <target dev='vdb' bus='virtio'/> >> > > > > > > -- >> > > > > > > >> > > > > > > STOP and START VM = after SQL >> > > > > > > >> > > > > > > root@ix1-c7-4:~# virsh dumpxml i-2-10-VM | grep cache -A2 >> > > > > > > <driver name='qemu' type='qcow2' cache='writeback'/> >> > > > > > > <source file='/mnt/63a3ae7b-9ea9-3884- >> > > > > a772-1ea939ef6ec3/1b655159- >> > > > > > > ae10-41cf-8987-f1cfb47fe453'/> >> > > > > > > <target dev='vda' bus='virtio'/> >> > > > > > > -- >> > > > > > > <driver name='qemu' type='qcow2' cache='writeback'/> >> > > > > > > <source file='/mnt/63a3ae7b-9ea9-3884- >> > > > > a772-1ea939ef6ec3/09bdadcb- >> > > > > > > ec6e-4dda-b37b-17b1a749257f'/> >> > > > > > > <target dev='vdb' bus='virtio'/> >> > > > > > > -- >> > > > > > > >> > > > > > > >> > > > > > > >> > > > > > > On 20 February 2018 at 14:03, Rafael Weingärtner < >> > > > > > > rafaelweingart...@gmail.com> wrote: >> > > > > > > >> > > > > > >> I have no idea how it can change the performance. If you >> look at >> > > the >> > > > > > >> content of the commit you provided, it is only the commit >> that >> > > > enabled >> > > > > > the >> > > > > > >> use of getCacheMode from disk offerings. However, it is not >> > > exposing >> > > > > any >> > > > > > >> way to users to change that value/configuration in the >> > database. I >> > > > > might >> > > > > > >> have missed it; do you see any API methods that receive the >> > > > parameter >> > > > > > >> "cacheMode" and then pass this parameter to a "diskOffering" >> > > object, >> > > > > and >> > > > > > >> then persist/update this object in the database? >> > > > > > >> >> > > > > > >> May I ask how are you guys changing the cacheMode >> configuration? >> > > > > > >> >> > > > > > >> On Tue, Feb 20, 2018 at 9:56 AM, Paul Angus < >> > > > paul.an...@shapeblue.com >> > > > > > >> > > > > > >> wrote: >> > > > > > >> >> > > > > > >> > I'm working with some guys who are experimenting with the >> > > setting >> > > > as >> > > > > > if >> > > > > > >> > definitely seems to change the performance of data disks. >> It >> > > also >> > > > > > >> changes >> > > > > > >> > the XML of the VM which is created. >> > > > > > >> > >> > > > > > >> > p.s. >> > > > > > >> > I've found this commit; >> > > > > > >> > >> > > > > > >> > https://github.com/apache/clou >> dstack/commit/1edaa36cc68e845a >> > > > > > >> 42339d5f267d49 >> > > > > > >> > c82343aefb >> > > > > > >> > >> > > > > > >> > so I've got something to investigate now, but API >> > documentation >> > > > must >> > > > > > >> > definitely be askew. >> > > > > > >> > >> > > > > > >> > >> > > > > > >> > >> > > > > > >> > paul.an...@shapeblue.com >> > > > > > >> > www.shapeblue.com >> > > > > > >> > 53 Chandos Place, Covent Garden, London WC2N 4HSUK >> > > > > > >> > @shapeblue >> > > > > > >> > >> > > > > > >> > >> > > > > > >> > >> > > > > > >> > >> > > > > > >> > -----Original Message----- >> > > > > > >> > From: Rafael Weingärtner [mailto:rafaelweingartner@gmai >> l.com] >> > > > > > >> > Sent: 20 February 2018 12:31 >> > > > > > >> > To: dev <dev@cloudstack.apache.org> >> > > > > > >> > Subject: Re: Caching modes >> > > > > > >> > >> > > > > > >> > This cache mode parameter does not exist in >> > > > "CreateDiskOfferingCmd" >> > > > > > >> > command. I also checked some commits from 2, 3, 4 and 5 >> years >> > > ago, >> > > > > and >> > > > > > >> > this parameter was never there. If you check the API in >> [1], >> > you >> > > > can >> > > > > > see >> > > > > > >> > that it is not an expected parameter. Moreover, I do not >> see >> > any >> > > > use >> > > > > > of >> > > > > > >> > "setCacheMode" in the code (in case it is updated by some >> > other >> > > > > > method). >> > > > > > >> > Interestingly enough, the code uses "getCacheMode". >> > > > > > >> > >> > > > > > >> > In summary, it is not a feature, and it does not work. It >> > looks >> > > > like >> > > > > > >> some >> > > > > > >> > leftover from dark ages when people could commit anything >> and >> > > then >> > > > > > they >> > > > > > >> > would just leave a half implementation there in our code >> base. >> > > > > > >> > >> > > > > > >> > [1] >> > > > > > >> > https://cloudstack.apache.org/api/apidocs-4.11/apis/ >> > > > > > >> > createDiskOffering.html >> > > > > > >> > >> > > > > > >> > >> > > > > > >> > On Tue, Feb 20, 2018 at 9:19 AM, Andrija Panic < >> > > > > > andrija.pa...@gmail.com >> > > > > > >> > >> > > > > > >> > wrote: >> > > > > > >> > >> > > > > > >> > > I can also assume that "cachemode" as API parameter is >> not >> > > > > > supported, >> > > > > > >> > > since when creating data disk offering via GUI also >> doesn't >> > > set >> > > > it >> > > > > > in >> > > > > > >> > DB/table. >> > > > > > >> > > >> > > > > > >> > > CM: create diskoffering name=xxx displaytext=xxx >> > > > > > storagetype=shared >> > > > > > >> > > disksize=1024 cachemode=writeback >> > > > > > >> > > >> > > > > > >> > > this also does not set cachemode in table... my guess >> it's >> > not >> > > > > > >> > > implemented in API >> > > > > > >> > > >> > > > > > >> > > Let me know if I can help with any testing here. >> > > > > > >> > > >> > > > > > >> > > Cheers >> > > > > > >> > > >> > > > > > >> > > On 20 February 2018 at 13:09, Andrija Panic < >> > > > > > andrija.pa...@gmail.com> >> > > > > > >> > > wrote: >> > > > > > >> > > >> > > > > > >> > > > Hi Paul, >> > > > > > >> > > > >> > > > > > >> > > > not helping directly answering your question, but here >> are >> > > > some >> > > > > > >> > > > observations and "warning" if client's are using >> > write-back >> > > > > cache >> > > > > > on >> > > > > > >> > > > KVM level >> > > > > > >> > > > >> > > > > > >> > > > >> > > > > > >> > > > I have (long time ago) tested performance in 3 >> > combinations >> > > > > (this >> > > > > > >> > > > was not really thorough testing but a brief testing >> with >> > FIO >> > > > and >> > > > > > >> > > > random IO WRITE) >> > > > > > >> > > > >> > > > > > >> > > > - just CEPH rbd cache (on KVM side) >> > > > > > >> > > > i.e. [client] >> > > > > > >> > > > rbd cache = true >> > > > > > >> > > > rbd cache writethrough until flush = >> true >> > > > > > >> > > > #(this is default 32MB per volume, >> afaik >> > > > > > >> > > > >> > > > > > >> > > > - just KMV write-back cache (had to manually edit >> > > > disk_offering >> > > > > > >> > > > table to activate cache mode, since when creating new >> disk >> > > > > > offering >> > > > > > >> > > > via GUI, the disk_offering tables was NOT populated >> with >> > > > > > >> > > > "write-back" sertting/value >> > > > > > >> > > ! ) >> > > > > > >> > > > >> > > > > > >> > > > - both CEPH and KVM write-back cahce active >> > > > > > >> > > > >> > > > > > >> > > > My observations were like following, but would be good >> to >> > > > > actually >> > > > > > >> > > confirm >> > > > > > >> > > > by someone else: >> > > > > > >> > > > >> > > > > > >> > > > - same performance with only CEPH caching or with only >> KVM >> > > > > caching >> > > > > > >> > > > - a bit worse performance with both CEPH and KVM >> caching >> > > > active >> > > > > > >> > > > (nonsense combination, I know...) >> > > > > > >> > > > >> > > > > > >> > > > >> > > > > > >> > > > Please keep in mind, that some ACS functionality, KVM >> > > > > > >> > > > live-migrations on shared storage (NFS/CEPH) are NOT >> > > supported >> > > > > > when >> > > > > > >> > > > you use KVM write-back cache, since this is considered >> > > > "unsafe" >> > > > > > >> > migration, more info here: >> > > > > > >> > > > https://doc.opensuse.org/documentation/leap/ >> > virtualization/ >> > > > > > >> > > html/book.virt/ >> > > > > > >> > > > cha.cachemodes.html#sec.cache.mode.live.migration >> > > > > > >> > > > >> > > > > > >> > > > or in short: >> > > > > > >> > > > " >> > > > > > >> > > > The libvirt management layer includes checks for >> migration >> > > > > > >> > > > compatibility based on several factors. If the guest >> > storage >> > > > is >> > > > > > >> > > > hosted on a clustered file system, is read-only or is >> > marked >> > > > > > >> > > > shareable, then the cache mode is ignored when >> determining >> > > if >> > > > > > >> > > > migration can be allowed. Otherwise libvirt will not >> allow >> > > > > > migration >> > > > > > >> > > > unless the cache mode is set to none. However, this >> > > > restriction >> > > > > > can >> > > > > > >> > > > be overridden with the “unsafe” option to the migration >> > > APIs, >> > > > > > which >> > > > > > >> > > > is also supported by virsh, as for example in >> > > > > > >> > > > >> > > > > > >> > > > virsh migrate --live --unsafe >> > > > > > >> > > > " >> > > > > > >> > > > >> > > > > > >> > > > Cheers >> > > > > > >> > > > Andrija >> > > > > > >> > > > >> > > > > > >> > > > >> > > > > > >> > > > On 20 February 2018 at 11:24, Paul Angus < >> > > > > > paul.an...@shapeblue.com> >> > > > > > >> > > wrote: >> > > > > > >> > > > >> > > > > > >> > > >> Hi Wido, >> > > > > > >> > > >> >> > > > > > >> > > >> This is for KVM (with Ceph backend as it happens), the >> > API >> > > > > > >> > > >> documentation is out of sync with UI capabilities, so >> I'm >> > > > > trying >> > > > > > to >> > > > > > >> > > >> figure out if we >> > > > > > >> > > >> *should* be able to set cacheMode for root disks. It >> > seems >> > > > to >> > > > > > make >> > > > > > >> > > quite a >> > > > > > >> > > >> difference to performance. >> > > > > > >> > > >> >> > > > > > >> > > >> >> > > > > > >> > > >> >> > > > > > >> > > >> paul.an...@shapeblue.com >> > > > > > >> > > >> www.shapeblue.com >> > > > > > >> > > >> 53 Chandos Place, Covent Garden, London WC2N 4HSUK >> > > > @shapeblue >> > > > > > >> > > >> >> > > > > > >> > > >> >> > > > > > >> > > >> >> > > > > > >> > > >> >> > > > > > >> > > >> -----Original Message----- >> > > > > > >> > > >> From: Wido den Hollander [mailto:w...@widodh.nl] >> > > > > > >> > > >> Sent: 20 February 2018 09:03 >> > > > > > >> > > >> To: dev@cloudstack.apache.org >> > > > > > >> > > >> Subject: Re: Caching modes >> > > > > > >> > > >> >> > > > > > >> > > >> >> > > > > > >> > > >> >> > > > > > >> > > >> On 02/20/2018 09:46 AM, Paul Angus wrote: >> > > > > > >> > > >> > Hey guys, >> > > > > > >> > > >> > >> > > > > > >> > > >> > Can anyone shed any light on write caching in >> > CloudStack? >> > > > > > >> > cacheMode >> > > > > > >> > > >> is available through the UI for data disks (but not >> root >> > > > > disks), >> > > > > > >> but >> > > > > > >> > not >> > > > > > >> > > >> documented as an API option for data or root disks >> > > (although >> > > > is >> > > > > > >> > > documented >> > > > > > >> > > >> as a response for data disks). >> > > > > > >> > > >> > >> > > > > > >> > > >> >> > > > > > >> > > >> What hypervisor? >> > > > > > >> > > >> >> > > > > > >> > > >> In case of KVM it's passed down to XML which then >> passes >> > it >> > > > to >> > > > > > >> > Qemu/KVM >> > > > > > >> > > >> which then handles the caching. >> > > > > > >> > > >> >> > > > > > >> > > >> The implementation varies per hypervisor, so that >> should >> > be >> > > > the >> > > > > > >> > > question. >> > > > > > >> > > >> >> > > > > > >> > > >> Wido >> > > > > > >> > > >> >> > > > > > >> > > >> >> > > > > > >> > > >> > #huh? >> > > > > > >> > > >> > >> > > > > > >> > > >> > thanks >> > > > > > >> > > >> > >> > > > > > >> > > >> > >> > > > > > >> > > >> > >> > > > > > >> > > >> > paul.an...@shapeblue.com >> > > > > > >> > > >> > www.shapeblue.com >> > > > > > >> > > >> > 53 Chandos Place, Covent Garden, London WC2N 4HSUK >> > > > > @shapeblue >> > > > > > >> > > >> > >> > > > > > >> > > >> > >> > > > > > >> > > >> > >> > > > > > >> > > >> >> > > > > > >> > > > >> > > > > > >> > > > >> > > > > > >> > > > >> > > > > > >> > > > -- >> > > > > > >> > > > >> > > > > > >> > > > Andrija Panić >> > > > > > >> > > > >> > > > > > >> > > >> > > > > > >> > > >> > > > > > >> > > >> > > > > > >> > > -- >> > > > > > >> > > >> > > > > > >> > > Andrija Panić >> > > > > > >> > > >> > > > > > >> > >> > > > > > >> > >> > > > > > >> > >> > > > > > >> > -- >> > > > > > >> > Rafael Weingärtner >> > > > > > >> > >> > > > > > >> >> > > > > > >> >> > > > > > >> >> > > > > > >> -- >> > > > > > >> Rafael Weingärtner >> > > > > > >> >> > > > > > > >> > > > > > > >> > > > > > > >> > > > > > > -- >> > > > > > > >> > > > > > > Andrija Panić >> > > > > > > >> > > > > > >> > > > > > >> > > > > > >> > > > > > -- >> > > > > > >> > > > > > Andrija Panić >> > > > > > >> > > > > >> > > > > >> > > > > >> > > > > -- >> > > > > Rafael Weingärtner >> > > > > >> > > > >> > > > >> > > > >> > > > -- >> > > > >> > > > Andrija Panić >> > > > >> > > >> > > >> > > >> > > -- >> > > Rafael Weingärtner >> > > >> > >> > >> > >> > -- >> > >> > Andrija Panić >> > >> >> >> >> -- >> Rafael Weingärtner >> > > > > -- > > Andrija Panić > -- Andrija Panić
