Deep dive into Kernel

Each row in /proc/$PID/maps describes a region of contiguous virtual memory in a process or thread. Each row has the following fields:address perms offset dev inode pathname 08048000-08056000 r-xp 00000000 03:0c 64593 /usr/sbin/gpm address - This is the starting and ending address of the region in the process's address spacepermissions - This describes how pages in the region can be accessed. Th..

DPDK receive performance Atom C2758 and E5-2609 core has same clock speed 2.4GHz.But the receiving performance has difference values, since Atom has much cache-misses. L2 Forwarding Performance BaremetalVM(IOMMU)VM(No IOMMU)VhostXeon(E5-2609 @ 2.4 GHz)13.66 Mpps(9179 Mbps) 7.46 Mpps(4777 Mbps)13.57 Mpps(9122 Mbps) Atom(C2758 @ 2.41GHz)9.78 Mpps(6576 Mbps) 9.63 Mpps(6476 Mbps)* SR-IOV w/o IOMMU (..

커널 컴파일 https://www.freebsd.org/doc/handbook/kernelconfig-building.html How to Contributehttps://www.freebsd.org/doc/en/articles/contributing/contrib-how.html Bug reporthttps://bugs.freebsd.org/bugzilla/

FreeBSD report:http://unix.derkeiler.com/Mailing-Lists/FreeBSD/net/2012-10/msg00095.html- link status 는 못찾는데 동작은 함 bug report:http://permalink.gmane.org/gmane.comp.networking.dpdk.devel/857 FreeBSD IXGBE pf driver 의 경우ix0: flags=8843 metric 0 mtu 1500 options=8407bb ether a0:36:9f:13:82:a8 nd6 options=29 media: Ethernet autoselect (10Gbase-Twinax ) status: active ethtool shows difference autoneg..

root@cnode01-m:~/suprem/qemu/scripts/kvm# modprobe msrroot@cnode01-m:~/suprem/qemu/scripts/kvm# ./vmxcapBasic VMX Information Revision 16 VMCS size 1024 VMCS restricted to 32 bit addresses no Dual-monitor support yes VMCS memory type 6 INS/OUTS instruction information yes IA32_VMX_TRUE_*_CTLS support yespin-based controls External interrupt exiting yes NMI exiting yes Virtual NMIs yes Activate V..

•Large Intel VT-d Pages •Adds 2 MB and 1 GB page sizes to Intel VT-d implementations •Matches current support for Extended Page Tables (EPT) •Ability to share CPU’s EPT page-table(with super-pages) with Intel VT-d •Benefits: •Less memory foot-print for I/O page-tables when using super-pages •Potential for improved performance – Due to shorter page-walks, allows hardware optimization for IOTLB •T..

XL710QDA2 (40G Ethernet card) x 2식 ($940 x 2 = $1880) 참조: http://www.colfaxdirect.com/store/pc/viewPrd.asp?idproduct=2232&idcategory=6 XLDACBL1 (QSFP+ Twinaxial Cable, 1 Meter) x 4식 ($128 x 4 = $512)http://www.colfaxdirect.com/store/pc/viewPrd.asp?idproduct=2235&idcategory=2

########### Trying to set two addresses to map the second region results in a startup error: root at ovdk1:/usr/src/dpdk-ovs# ./openvswitch/datapath/dpdk/build/ovs_dpdk -c 0x0f -n 4 --proc-type=primary --base-virtaddr=0x7f0f80000000,0x7f0e40000000 --socket-mem 2048,2048 -- -p 0x03 -h 2 --stats=1 --client_switching_core=1 --config="(0,0,2),(1,0,3)" EAL: invalid parameter for --base-virtaddr Usage..

IOMMU: Strategies for Mitigating the IOTLB Bottleneck - from Sixth Annual Workshop on the Interaction between Operating Systems and Computer Architecture- Nadav Ammit (@techion), Muli Ben-Yhhuda(@ibm), Ben-Ami Yassour(@ibm) The computational cost of the mapping and unmapping of memory regions in the DMAR units is therefore considered the main bottleneck. The IOMMU translates the virtual I/O addr..

https://www.usenix.org/sites/default/files/conference/protected-files/nsdi14_slides_hwang.pdf