========================================================================
 README for mTCP
========================================================================

mTCP is a highly scalable user-level TCP stack for multicore systems. 
mTCP source code is distributed under the Modified BSD License. For 
more detail, please refer to the LICENSE. The license term of io_engine 
driver and ported applications may differ from the mTCP’s.

========================================================================
 PREREQUISITE
========================================================================

We require the following libraries to run mTCP.
 - libps (PacketShader I/O engine library) OR libdpdk (Intel's DPDK package*) OR netmap driver
 - libnuma
 - libpthread
 - librt
 - libgmp (for DPDK/ONVM driver)
 Compling PSIO/DPDK/NETMAP/ONVM driver requires kernel headers.
  - For Debian/Ubuntu, try apt-get install linux-headers-$(uname -r)


* We have modified the dpdk package to export net_device stat data 
(for Intel-based Ethernet adapters only) to the OS. To achieve this, we have
created a new LKM dpdk-iface-kmod. We also
modified mk/rte.app.mk file to ease the compilation process of mTCP applications.
We recommend using our package for DPDK installation. 

========================================================================
 INCLUDED DIRECTORIES
========================================================================

mtcp - mtcp source code directory
mtcp/src - source code
mtcp/src/include - mTCP’s internal header files
mtcp/lib - library file
mtcp/include - header files that applications will use

io_engine - event-driven packet I/O engine (io_engine)
io_engine/driver - driver source code
io_engine/lib - io_engine library
io_engine/include - io_engine header files
io_engine/samples - sample io_engine applications (not mTCP’s)

dpdk - Intel's Data Plane Development Kit
dpdk/...

apps - mTCP applications
apps/example - example applications (see README)
apps/lighttpd-1.4.32 - mTCP-ported lighttpd (see INSTALL)
apps/apache_benchmark - mTCP-ported apache benchmark (ab) (see README-mtcp)

util - useful source code for applications

config - sample mTCP configuration files (may not be necessary)

========================================================================
 INSTALL GUIDES
========================================================================
mTCP can be prepared in three ways.

- PSIO VERSION -
----------------
1. make in io_engine/driver:
   	   # make
  - check ps_ixgbe.ko
  - please note that psio only runs on linux-2.6.x kernels
    (linux-2.6.32 ~ linux-2.6.38)

2. install the driver:
   	   # ./install.py <# cores> <# cores>
  - refer to http://shader.kaist.edu/packetshader/io_engine/
  - you may need to change the ip address in install.py:46

3. Setup mtcp library:
   	   # ./configure --with-psio-lib=<$path_to_ioengine>
	     ## e.g. ./configure --with-psio-lib=`echo $PWD`/io_engine
   	   # make
  - By default, mTCP assumes that there are 16 CPUs in your system.
    You can set the CPU limit, e.g. on a 8-core system, by using the following command:
    	   # ./configure --with-psio-lib=`echo $PWD`/io_engine CFLAGS="-DMAX_CPUS=8"
    Please note that your NIC should support RSS queues equal to the MAX_CPUS value
    (since mTCP expects a one-to-one RSS queue to CPU binding).	   
  - In case `./configure' script prints an error, run the
    following command; and then re-do step-3 (configure again):
    	   # autoreconf -ivf
  - check libmtcp.a in mtcp/lib
  - check header files in mtcp/include
  - check example binary files in apps/example

4. Check the configurations in apps/example
  - epserver.conf for server-side configuration
  - epwget.conf for client-side configuration
  - you may write your own configuration file for your application

5. Run the applications!


- DPDK VERSION -
----------------
1. Set up DPDK first.

       # bash setup_mtcp_dpdk_env.sh [<path to $RTE_SDK]]

   Press [14] to compile x86_64-native-linuxapp-gcc version
   Press [17] to install the driver
   Press [21] to setup 2048 2MB hugepages
   Press [23] to register the Ethernet ports
   Press [34] to quit the tool

  Only those devices will work with DPDK drivers that are listed
  on this page: http://dpdk.org/doc/nics. Please make sure that your
  NIC is compatible before moving on to the next step.

  We use dpdk-18.02/ as our DPDK driver. FYI, you can pass a different
  dpdk source directory as command line argument.
   
2. Next bring the dpdk-registered interfaces up, and then set RTE_SDK
and RTE_TARGET environment variables.
  
       # sudo ifconfig dpdk0 x.x.x.x netmask 255.255.255.0 up
       # export RTE_SDK=`echo $PWD`/dpdk
       # export RTE_TARGET=x86_64-native-linuxapp-gcc

3. Setup mtcp library:
	   # ./configure --with-dpdk-lib=$RTE_SDK/$RTE_TARGET
   	   # make

- By default, mTCP assumes that there are 16 CPUs in your system.
    You can set the CPU limit, e.g. on a 32-core system, by using the following command:
    	   # ./configure --with-dpdk-lib=$RTE_SDK/$RTE_TARGET CFLAGS="-DMAX_CPUS=32"
    Please note that your NIC should support RSS queues equal to the MAX_CPUS value
    (since mTCP expects a one-to-one RSS queue to CPU binding).
  - In case `./configure' script prints an error, run the
    following command; and then re-do step-4 (configure again):
    	   # autoreconf -ivf
  - checksum offloading in the NIC is now ENABLED (by default)!!!
    	     - this only works for dpdk at the moment
	     - use 
	       ./configure --with-dpdk-lib=$RTE_SDK/$RTE_TARGET --disable-hwcsum
	       to disable checksum offloading.
  - check libmtcp.a in mtcp/lib
  - check header files in mtcp/include
  - check example binary files in apps/example

5. Check the configurations in apps/example
  - epserver.conf for server-side configuration
  - epwget.conf for client-side configuration
  - you may write your own configuration file for your application

6. Run the applications!

7. You can revert back all your changes by running the following script.

       # bash setup_linux_env.sh [<path to $RTE_SDK]]
   
   Press [29] to unbind the Ethernet ports
   Press [30] to remove igb_uio.ko driver
   Press [33] to remove hugepage mappings
   Press [34] to quit the tool


- ONVM VERSION -
----------------

~NEW~: Now you can run mTCP applications (server + client) locally.
A local setup is useful when only 1 machine is available for the experiment. 
ONVM configurations are placed as `.conf` files in apps/example directory.
ONVM basics are explained in https://github.com/sdnfv/openNetVM.

**Before running the applications make sure that onvm_mgr is running.**
Also, no core overlap between applications and onvm_mgr is allowed.

1. Install openNetVM using the following instructions 
           https://github.com/sdnfv/openNetVM/blob/master/docs/Install.md

2. Next bring the dpdk-registered interfaces up. This can be setup using:
	   # sudo ifconfig dpdk0 x.x.x.x netmask 255.255.255.0 up

3. Setup mtcp library
	   # ./configure --with-dpdk-lib=$<path_to_dpdk> --with-onvm-lib=$<path_to_onvm_lib>
	   # e.g. ./configure --with-dpdk-lib=$RTE_SDK/$RTE_TARGET --with-onvm-lib=`echo $ONVM_HOME`/onvm
	   # make

  - By default, mTCP assumes that there are 16 CPUs in your system.
    You can set the CPU limit, e.g. on a 32-core system, by using the following command:
      # ./configure --with-dpdk-lib=$RTE_SDK/$RTE_TARGET --with-onvm-lib=$<path_to_onvm_lib> CFLAGS="-DMAX_CPUS=32"
    Please note that your NIC should support RSS queues equal to the MAX_CPUS value
    (since mTCP expects a one-to-one RSS queue to CPU binding).
    
  - In case `./configure' script prints an error, run the
    following command; and then re-do step-4 (configure again):
         # autoreconf -ivf
  - checksum offloading in the NIC is now ENABLED (by default)!!!
           - this only works for dpdk at the moment
       - use 
         ./configure --with-dpdk-lib=$RTE_SDK/$RTE_TARGET --disable-hwcsum
         to disable checksum offloading.
  - check libmtcp.a in mtcp/lib
  - check header files in mtcp/include
  - check example binary files in apps/example

5. Check the configurations in apps/example
  - epserver.conf for server-side configuration
  - epwget.conf for client-side configuration
  - you may write your own configuration file for your application

6. Run the applications!

7. You can revert back all your changes by running the following script.

       # bash setup_linux_env.sh
   
   Press [29] to unbind the Ethernet ports
   Press [30] to remove igb_uio.ko driver
   Press [33] to remove hugepage mappings
   Press [34] to quit the tool
   
 - Notes -
Once you have started onvm_mgr, sometimes an mTCP application may fail to get launched due
to a error(s) resembling the one mentioned below:

  # EAL: FATAL: Cannot init memory 
    OR
  # Cannot mmap memory for rte_config at [0x7ffff7fb6000], got [0x7ffff7e74000] - please use '--base-virtaddr' option
    OR
  # EAL: Cannot mmap device resource file /sys/bus/pci/devices/0000:06:00.0/resource3 to address: 0x7ffff7ff1000 

To prevent this, use the base virtual address parameter to run the ONVM manager, e.g.:

cd openNetVM/onvm
./go.sh 1,2,3 1 -s stdout -a 0x7f000000000


- NETMAP VERSION -
------------------
See README.netmap for details.

========================================================================
 TESTED ENVIRONMENTS
========================================================================

mTCP runs on Linux-based operating systems (2.6.x for PSIO) with generic 
x86_64 CPUs, but to help evaluation, we provide our tested environments 
as follows.

Intel Xeon E5-2690 octacore CPU @ 2.90 GHz
32 GB of RAM (4 memory channels)
10 GbE NIC with Intel 82599 chipset (specifically Intel X520-DA2)
Debian 6.0.7 (Linux 2.6.32-5-amd64)

Intel Core i7-3770 quadcore CPU @ 3.40 GHz
16 GB of RAM (2 memory channels)
10 GbE NIC with Intel 82599 chipset (specifically Intel X520-DA2)
Ubuntu 10.04 (Linux 2.6.32-47)

Event-driven PacketShader I/O engine (extended io_engine-0.2)
 - PSIO is currently only compatible with Linux-2.6.

We tested the DPDK version (polling driver) with Linux-3.13.0 kernel.
========================================================================
 NOTES
========================================================================

1. mTCP currently runs with fixed memory pools. That means, the size of
   TCP receive and send buffers are fixed at the startup and does not 
   increase dynamically. This could be performance limit to the large 
   long-lived connections. Be sure to configure the buffer size 
   appropriately to your size of workload.

2. The client side of mTCP supports mtcp_init_rss() to create an 
   address pool that can be used to fetch available address space in 
   O(1). To easily congest the server side, this function should be 
   called at the application startup.

3. The supported socket options are limited for right now. Please refer 
   to the mtcp/src/api.c for more detail.

4. The counterpart of mTCP should enable TCP timestamp.

5. mTCP has been tested with the following Ethernet adapters:

   1. Intel-82598		ixgbe		(Max-queue-limit: 16)
   2. Intel-82599		ixgbe		(Max-queue-limit: 16)
   3. Intel-I350		igb		(Max-queue-limit: 08)
   4. Intel-X710		i40e		(Max-queue-limit: ~)
   5. Intel-X722		i40e		(Max-queue-limit: ~)
 
========================================================================
 FREQUENTLY ASKED QUESTIONS
========================================================================

1. How can I quit the application?
  - Use ^C to gracefully shutdown the application. Two consecutive 
    ^C (separated by 1 sec) will force quit.

2. My application keeps printing "No route to 0.0.0.0"
  - Try to turn off your network-manager for xge*. The network manager 
    can override the IP configuration set by install.py in PSIO driver.

3. Can I statically set the routing or arp table?
  - Yes, mTCP allows static route and arp configuration. Go to the 
    config directory and see sample_route.conf or sample_arp.conf. 
    Copy and adapt it to your condition and link (ln -s) the config 
    directory to the application directory. mTCP will find 
    config/route.conf and config/arp.conf for static configuration.

========================================================================
 CAUTION
========================================================================

1. Do not remove I/O driver (ps_ixgbe/igb_uio) while running mTCP 
   applications. The application will panic!

2. Use the ps_ixgbe/dpdk driver contained in this package, not the one 
   from some other place (e.g., from io_engine github).

========================================================================

                   Contact: mtcp-user at list.ndsl.kaist.edu
                             April 2, 2015. 
                 EunYoung Jeong <notav at ndsl.kaist.edu>
		 M. Asim Jamshed <ajamshed at ndsl.kaist.edu>
