From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christian Ehrhardt Date: Fri, 28 Mar 2008 14:49:37 +0000 Subject: [kvm-ppc-devel] little initial performance measurement Message-Id: <47ED0581.5080201@linux.vnet.ibm.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To: kvm-ppc@vger.kernel.org ######## looking at the guest with kvmstat and at the host with vmstat ####= #### guest idle looks very busy - we need MSR[WE] support - good that jerone is = working on that already: kvmstat | dcr_exits | exits | light_exits | mmio_exits |re= mote_tlb_flush | signal_exits | | 0 | 23302 | 23250 | 0 | = 0 | 80 | | 0 | 24147 | 24064 | 0 | = 0 | 79 | | 0 | 24421 | 24303 | 0 | = 0 | 78 | vmstat procs -----------memory---------- ---swap-- -----io---- --system-- ----cpu-= --- r b swpd free buff cache si so bi bo in cs us sy i= d wa 1 0 0 183292 0 26196 0 0 0 0 130 169 2 99 = 0 0 1 0 0 183292 0 26196 0 0 0 0 112 150 2 98 = 0 0 1 0 0 183292 0 26196 0 0 0 0 112 151 1 100 = 0 0 When doing some small IO in the guest we see a bit host userspace activity = (4%) - but not much, therefore I do not expect IO as the part that slows us= down atm. procs -----------memory---------- ---swap-- -----io---- --system-- ----cpu= ---- r b swpd free buff cache si so bi bo in cs us sy = id wa 1 0 0 182932 0 26196 0 0 0 0 308 159 4 96 = 0 0 The portion of mmio exits to light exits is still <1% ######## some basic perf tests for virtio ######## Compare speed of guest and host (very simple tests, host measured without r= unning guest) I/O - dd on nfs rm /root/testddfile; time dd if=3D/dev/urandom of=3D/root/testddfile bs 48= countP0 ping for basic latency bash-3.00# ping 192.168.1.2 -c 4 ------Guest------ -----Host----- DD DD 500+0 records in 500+0 records in 500+0 records out 500+0 records out =09 real 0m22.552s real 0m0.947s user 0m1.600s user 0m0.004s sys 0m20.864s sys 0m0.856s 64 bytes from 192.168.1.2: icmp_seq=3D0 ttld time=12.3 ms 64 bytes from 192= .168.1.2: icmp_seq=3D0 ttld time=3D0.165 ms 64 bytes from 192.168.1.2: icmp_seq=3D1 ttld time=3D8.14 ms 64 bytes from 1= 92.168.1.2: icmp_seq=3D1 ttld time=3D0.153 ms 64 bytes from 192.168.1.2: icmp_seq=3D2 ttld time=3D7.04 ms 64 bytes from 1= 92.168.1.2: icmp_seq=3D2 ttld time=3D0.143 ms 64 bytes from 192.168.1.2: icmp_seq=3D3 ttld time=3D7.08 ms 64 bytes from 1= 92.168.1.2: icmp_seq=3D3 ttld time=3D0.147 ms =3D> latency and throughput are very bad atm. We need to find out where this speed is lost. Possibly this IO emulation is= slow for us, but we also have some "waits" in the boot process which are d= efinetly not I/O bound (e.g. TLB trashing ?) and we know that our guest idl= e is a busy wait for us until we have implemented that code for MSR[WE]. A little Timing check: sleep 30s vs. real clock 30s Host: Guest: TODO Little userspace app that heavily uses memory: I also think about a small userpsace app that allocate&uses memory heavily = to push our tlb code e.g. to test any improvements we make there. I have a similar app here and will post it once I have adaptedt it to our n= eeds and tested it. Next mail will be a patch to extend our kvmstat informations about light ex= its. --=20 Gr=FCsse / regards,=20 Christian Ehrhardt IBM Linux Technology Center, Open Virtualization ------------------------------------------------------------------------- Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace _______________________________________________ kvm-ppc-devel mailing list kvm-ppc-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-ppc-devel