11.1 Disabling and Enabling Power Management
Package C3 (PC3), and Package C6 (PC6) are power management states that are entered when the coprocessor is idle for a period of time. Power management states are enabled by default in Intel MPSS. Under normal circumstances, the host sends traffic to awaken the coprocessor and resume execution. The following instructions indicate how to disable and re-enable power management.PREREQUISITES:
The following settings can only be modified by the root user:
To disable power management package states and allow successful execution of an application that uses the sleep() function on the coprocessor, change the line in each /etc/mpss/micN.conf file to this:
PowerManagement "cpufreq_on;corec6_off;pc3_off;pc6_off"
To re-enable power management, change the line in each /etc/mpss/micN.conf file to this:
PowerManagement "cpufreq_on;corec6_on;pc3_on;pc6_on"
Where N is an integer number (0, 1, 2, 3, etc.) that identifies each coprocessor installed in the system.
The values may also be changed with the micctrl --pm=<value> command. To disable power management, set <value> to off. To enable, set <value> to default.
NOTE: Restarting of the coprocessor(s) is required after modifications to the micN.conf files. Use the following command to restart:
[host]# micctrl -R
11.2 Disabling and Enabling the Memory Control
Group (cgroup)
The memory Control Group is disabled by default in this release, but it can be enabled in the /etc/mpss/micN.conf files. Enabling the memory cgroup decreases the amount of memory available to applications on the coprocessor by about 120MB.
(Intel® MPSS)
The following settings can only be modified by the root user:
To enable the memory cgroup, set the Cgroup memory variable to enabled in the /etc/mpss/micN.conf files and then restart the Intel MPSS service:
1) In /etc/mpss/micN.conf: Cgroup memory=enabled 2) Restart the Intel MPSS service:
[host]# 1service mpss restart
To disable the memory cgroup, set the Cgroup memory variable to disabled in the /etc/mpss/micN.conf files and then restart the Intel MPSS service:
1) In /etc/mpss/micN.conf: Cgroup memory=disabled 2) Restart the Intel MPSS service:
[host]# 1service mpss restart
11.3 Installing Card Side RPMs
To install card side RPMs, use one of the procedures outlined below in Sections 11.3.1
through 11.3.3.
Currently, the mpss-[version number]-k1om.tar file contains the card-side RPMs. Go to the Intel® Developer Zone website (Intel® DZ):
http://software.intel.com/en-us/articles/intel-manycore-platform-software-stack-mpss.
Download the mpss-[version number]-k1om.tar file from the Software for Coprocessor OS link associated with your Intel MPSS release.
In order to use zypper to install RPM files located on the card side, coreutils must first be installed.
To do this:
[host]$ xvf mpss-[version number]-k1om.tar [host]$ cd mpss-[version number]/k1om [host]# scp coreutils*.rpm micN:. [host]# scp libgmp*.rpm micN:. [host]# ssh micN
[micN]# rpm -ihv coreutils*.rpm libgmp*.rpm
11.3.1 Copy RPMs to the Card Using SCP
Steps:
1) Extract the mpss-[version number]-k1om.tar file. This will create the mpss-[version number]/k1om directory.
Important Considerations
2) Change to the extracted folder.
[host]$ cd mpss-[version number]/k1om 3) SCP the RPMs to the card.
[host]# scp <rpm_packages> micN:/tmp
4) SSH to the card.
[host]# ssh micN
5) Install the RPMs via rpm or zypper utility (zypper example shown).
[micN]# zypper install /tmp/<rpm_package_name>
6) Repeat steps 3-5 for the remaining card(s).
Where N is an integer number (0, 1, 2, 3, etc.) that identifies each coprocessor installed in the system.
11.3.2 Copy RPMs to Card Using a Repo and Zypper (via HTTP)
Set up an http server (reachable from the card) offering Intel MPSS RPM repodata. The steps in this section require that Python and the createrepo tool be previously installed.
Steps:
1) Create a folder to place the Intel MPSS tarball.
[host]$ mkdir mpss-repo; cd mpss-repo
2) Go to the Intel® Developer Zone website (Intel® DZ): http://software.intel.com/en-
us/articles/intel-manycore-platform-software-stack-mpss.
Download the mpss-[version number]-k1om.tar file from the Software for
Coprocessor OS link associated with your Intel MPSS release into the folder recently created.
3) Extract the tarball file.
[host]$ tar xvf mpss-[version number]-k1om.tar
4) Change to the extracted folder.
[host]$ cd mpss-[version number]
5) Use the createrepo tool to create a new repo.
[host]$ createrepo .
6) Start the http server as follows:
[host]# python -m SimpleHTTPServer
7) Create a service to provide RPM installation at every card boot. To achieve this, create a folder under /var/mpss/common/etc/init.d
(Intel® MPSS)
8) Under /var/mpss/common/etc/init.d create the service file named install-ganglia- service as follows (example shown applies to GANGLIA* installation):
#!/bin/sh
### BEGIN INIT INFO
# Provides: install-ganglia-service # Required-Start:
# Required-Stop: $local_fs # Default-Start: S
# Default-Stop: 0 6
# Short-Description: Load node dependencies before notified as online
# Description: Load node dependencies before notified as online
zypper ar http://host:8000 k1om-mpss-[version number] (this line should be edited with environment specific information)
zypper -q --non-interactive --no-gpg-checks install ganglia zypper -q --non-interactive --no-gpg-checks install mpss-ganglia
9) Attach this init script to the appropriate runlevel so that Ganglia*’s monitoring functionality will be installed every time the Coprocessor starts. (Runlevel 5.) [host]# mkdir –p /var/mpss/common/etc/rc5.d
[host]# cd /var/mpss/common/etc/rc5.d
[host]# ln –s ../init.d/install-ganglia-service S95install-ganglia-service
[host]# chmod 0755 /var/mpss/common/etc/init.d/install- ganglia-service
10. Restart the mpss service.
[host]# service mpss restart
11.3.3 Use the Micctrl Utility
Steps:
1) In 3.x-based releases, place the RPM(s) for the card in a known location on the host. 2) Execute the micctrl command:
[host]# micctrl --overlay=rpm \
--source=<location of file> --state=on
Where location is the absolute path to a single RPM or a directory where all RPMs
contained in it are installed on the card at boot. The state parameter specifies whether or not to include the RPM(s) on the file system.
NOTE: When using the micctrl utility to install card side RPMs, it is not necessary to start the ofed-mic service (Section 2.5, step 4 is not required).
Important Considerations
11.4 BIOS Setting and Process Affinity
BIOS setting and process affinity have a significant performance impact on SCIF. Without the correct BIOS and user process affinity settings, you can expect to see considerable performance penalties.
11.4.1 BIOS Setting
Make sure Intel® Turbo Boost Technology is enabled in the BIOS.
11.4.2 Process Affinity
In the Intel® Xeon Phi™ product, each coprocessor belongs to a particular NUMA (non- uniform memory access) node. A device that is connected to a particular node can access the memory in this node faster than it can access the memory in the other nodes. To get the maximum SCIF bandwidth, ensure your process runs on the same node as the coprocessor you communicate with by setting the process affinity.
(Intel® MPSS)