Re: [ovirt-devel] Discussion VM CPU pinning and NUMA CPU pinning

-----Original Message----- From: Gilad Chaplik [mailto:gchaplik@redhat.com] Sent: Thursday, May 15, 2014 8:07 PM To: Liao, Chuan (Jason Liao, HPservers-Core-OE-PSC) Cc: devel(a)ovirt.org; Doron Fediuck; Martin Sivák; Juan Hernandez; Malini Rao; Vinod, Chegu; Liang, Shang-Chun (David Liang, HPservers-Core-OE-PSC); Shi, Xiao-Lei (Bruce, HP Servers-PSC-CQ) Subject: Re: Discussion VM CPU pinning and NUMA CPU pinning Can you please be more specific on how to model RESTful API, with regards to CPU and CPU-pinning. Thanks, Gilad. ----- Original Message ----- > From: "Chuan Liao (Jason Liao, HPservers-Core-OE-PSC)" <chuan.liao(a)hp.com&gt; > To: devel(a)ovirt.org > Cc: "Doron Fediuck" <dfediuck(a)redhat.com&gt;, "Gilad Chaplik" <gchaplik(a)redhat.com&gt;, "Martin Sivák" <msivak(a)redhat.com&gt;, > "Juan Hernandez" <juan.hernandez(a)redhat.com&gt;, "Malini Rao" <mrao(a)redhat.com&gt;, "Chegu Vinod" <chegu_vinod(a)hp.com&gt;, > "Shang-Chun Liang (David Liang, HPservers-Core-OE-PSC)" <shangchun.liang(a)hp.com&gt;, "Xiao-Lei Shi (Bruce, HP > Servers-PSC-CQ)" <xiao-lei.shi(a)hp.com&gt; > Sent: Thursday, May 15, 2014 2:50:23 PM > Subject: Discussion VM CPU pinning and NUMA CPU pinning > > Hi All, > > Now we are working on the NUMA tune feature development for oVirt 3.5. This > feature allow user to configure the vCPU pining according to host CPU/NUMA > topology to get the best performance for created VM. But this will impact > the current function of vCPU pining. Now, we are looking for a solution to > consolidate the conflict. We want to start an open discussion about VM CPU > pinning (the current design) and NUMA CPU pining (new feature we are working > on) in developer list: > > Background: > Concept: > > 1. VM CPU pinning: the exist feature in current oVirt, which allow user > to configure the VM vCPU pinning over ovirt, user can configure vCPU pining > independently without NUMA tune. > > 2. NUMA CPU pinning: allow user to configure the vCPU pining according > to host NUMA topology to get the best performance for created VM > > 3. vNode: Virtual NUMA node ( User configured ) > > 4. pNode: host physical NUMA node ( Get capability from host ) > Notice: > > 1. NUMA tuning feature and CPU pinning feature are individually in > libvirt ( ovirt backend ). > > 2. User could configure VM CPU pining individually without NUMA tune > setup. > > 3. When configuring NUMA tuning feature, user need to configure VM NUMA > tuning ( vNode pinto pNode & tuning mode ) and VM CPU pinning ( NUMA > included ) to get optimized VM performance, otherwise VM will have low > performance. > > We have two proposal now for this issue. Please give us some comments and > your feedback, thanks. > > Solution 1: > GUI: > Transform between the CPU pinning text and a structure which will be used in > NUMA CPU pinning configure page. > And then save the CPU pinning text to the current VM CPU pinning field of > VM. > Restful: > Transform between the CPU pinning text and a structure which will be used in > restful NUMA CPU pinning. > And then save the CPU pinning text to the current VM CPU pinning field of VM. > Broker: > Remove temporary solution(See the current implementation as below) and follow > previous cpupin configuration procedure. > > Solution 2: > GUI: > If current VM CPU pinning is configured, when user open NUMA CPU pinning > configure page, he will get a warning message. If he continues to configure > NUMA CPU pinning and save the data, the current VM CPU pinning > configuration will be cleared. > NUMA CPU pinning configured data will be saved as new structure individually > without changing current VM CPU pinning configuration. > Restful: > Configure NUMA CPU pinning and then save the data with the new NUMA CPU > pinning structure. > Entity and Database: > Individually NUMA CPU pinning entities and data structure. > Broker: > NUMA CPU pinning configuration will be first considered to use. If > it's not configured, it will use the current VM CPU pinning. > > Solution 1 The CPU pining data is consistent but the code logic is very > complex. > Solution 2 have better adaptive and better data structure. This is the way we > preferred. > > We are appreciated that anybody could give us your comments or the better > solution you have. > > > > The below is the current implementation for your reference: > VM CPU pinning feature > GUI: > User input vCPU pining configure data with formatted text. > Restful: > User configure CpuTune and VCpuPin model with mapper to CPU pinning text. > Entity and Database: > CPU pinning is String property. > Broker: > Generate structure of cputune ( libvirt format ) from CPU pining string > property. > NUMA tuning feature > GUI: > User can drag & drop virtual NUMA node to host NUMA node ( pin to or remove > pin to ). > Restful: > Add/update/remove virtual NUMA node with property of pin to host NUMA node > index. > Design NUMACPU model under NUMA node for extend. > Entity and Database: > Individually NUMA node entities ( vNode extend pNode ) and store procedure. > Broker: > Generate structure of numatune, cpu/numa ( libvirt format ) from NUMA node > entities. > Temporary solution prevent Notice 3 > Broker: > Generate right structure of cputune ( libivirt format ) from NUMA node > entities ( vNode pinto pNode ) > Limitation: > This structure of cputune will not get the best performance of vNode. > > Best Regards, > Jason Liao > >