On Thu, May 15, 2025, Sairaj Kodilkar wrote: > Hi Sean, > > We ran few tests with following setup A few!!?!? This is awesome! Thank you, I greatly appreciate the testing! > * Turin system with 2P, 192 cores each (SMT enabled, Total 768) > * 4 NVMEs of size 1.7 attached to a single IOMMU > * Total RAM 247 GiB > * Qemu version : 9.1.93 > * Guest kernel : 6.14-rc7 > * FIO random reads with 4K blocksize and libai > > With above setup we measured the Guest nvme interrupts, IOPS, GALOG interrupts > and GALOG entries for 60 seconds with and without your changes. > > Here are the results, > > VCPUS = 32, Jobs per NVME = 8 > ============================================================================================== > w/o Sean's patches w/ Sean's patches Percent change > ---------------------------------------------------------------------------------------------- > Guest Nvme interrupts 123,922,860 124,559,110 0.51% > IOPS (in kilo) 4,795 4,796 0.04% > GALOG Interrupts 40,245 164 -99.59% > GALOG entries 42,040 169 -99.60% > ---------------------------------------------------------------------------------------------- > > > VCPUS = 64, Jobs per NVME = 16 > ============================================================================================== > w/o Sean's patches w/ Sean's patches Percent change > ---------------------------------------------------------------------------------------------- > Guest Nvme interrupts 99,483,339 99,800,056 0.32% > IOPS (in kilo) 4,791 4,798 0.15% > GALOG Interrupts 47,599 11,634 -75.56% > GALOG entries 48,899 11,923 -75.62% > ---------------------------------------------------------------------------------------------- > > > VCPUS = 192, Jobs per NVME = 48 > ============================================================================================== > w/o Sean's patches w/ Sean's patches Percent change > ---------------------------------------------------------------------------------------------- > Guest Nvme interrupts 76,750,310 78,066,512 1.71% > IOPS (in kilo) 4,751 4,749 -0.04% > GALOG Interrupts 56,621 54,732 -3.34% > GALOG entries 59,579 56,215 -5.65% > ---------------------------------------------------------------------------------------------- > > > The results show that patches have significant impact on the number of posted > interrupts at lower vCPU count (32 and 64) while providing similar IOPS and > Guest NVME interrupt rate (i.e. patches do not regress). > > Along with the performance evaluation, we did sanity tests such with AVIC, > x2AVIC and kernel selftest. All tests look good. > > For AVIC related patches: > Tested-by: Sairaj Kodilkar <sarunkod@xxxxxxx> > > Regards > Sairaj Kodilkar >
