Content in Intel Communities

Software Managed Coherence for SCC Release

webadmin@intel.com — Mon, 10 Dec 2012 07:12:55 GMT

The Single Chip Cloud Computer s a 48-core concept vehicle created by Intel Labs and used by hundreds of researchers worldwide for many-core software innovation. Software Managed Coherence (SMC) for SCC provides a shared virtual memory space for processor cores in the SCC. The SMC research software explores solutions to several many-core challenges. First, it is becoming more difficult to design and verify efficient hardware memory coherence for many-core processors as core counts scale to 10s-100s fo cores. Also, when multiple applications run on a single many-core chip it may require coherence support on the cores they are running on, but likely not between the applications. SMC enables dynamically reconfigurable coherence domains which is difficult to support with a hardware-only implementation. Lastly, hardware coherence is complex for heterogeneous platforms like combined CPU-GPU systems. Software Managed Coherence could make better use of silicon, efficiently support emerging applications, dynamically reconfigure coherence domain, and most importantly, still be able to provide performance comparable to hardware coherence.

The software is available as an anonymous export from the SCC public SVN.

svn export http://marcbug.scc-dc.com/svn/repository/tags/SMC_V1.0/

Message was edited by: Ted Kubaska ... 10s changed to 10s-100s

Howto_UseSCCBugzilla

webadmin@intel.com — Thu, 14 Jun 2012 00:21:15 GMT

MPI on the SCC

webadmin@intel.com — Fri, 01 Jun 2012 09:14:18 GMT

We now have a version of RCKMPI on the SCC. If you are interested in MPI on the SCC, please answer this thread. We can make it available for download through our public svn. This is a new thing and getting user input would be very helpful to us. If the interest in MPI is strong, I'll make a subcommunity specifically for discussing it.

sccKit 1.4.2 Beta is available

webadmin@intel.com — Wed, 23 May 2012 01:20:33 GMT

We’re starting a sccKit 1.4.2 beta. If you want to participate in this beta please create a Bugzilla bug in the ADD ME to the SCCKIT BETA 1.4.2 product.

http://marcbug.scc-dc.com/bugzilla3/

This is an informal beta. There are no beta reports to file.

The compressed tarfile that contains the sccKit 1.4.2 beta software is available for download from our public SVN,

http://marcbug.scc-dc.com/svn/repository/tarballs/ . The file is called sccKit_1.4.2.tar.bz2.

We’ll officially start the beta on Jan 9, 2012 and run it for one month until Feb 6, 2012. We will release the software if there are no P1 open bugs. Recall that our Bugzilla bugs have both severity and priority. Severity is determined by the user and is one of (blocker, critical, major, normal, minor, and trivial). The Bugzilla home page defines these terms. Priority is determined by Intel; it is one of the following (P1, P2, P3, and P5). P5 indicates that priority is not yet set. P1 means we must fix to release; P2 means we will fix, but an open P2 will not hold up the release; P3 means we will not fix.

The first goal is, of course, to check that your applications continue to work with this new release. Once you have verified that, you might consider taking advantage of the new features.

We will shortly follow this announcement with installation instructions and a description of new 1.4.2 features. In summary the installation is much like installing 1.4.1.3 with eMAC enabled. You must be root to install sccKit 1.4.2.

Copy sccKit_1.4.2.tar.bz2 to /opt/sccKit and untar it.
Remove the current link and remake it to point to 1.4.2.
Ensure that /opt/sccKit/1.4.2/bin is in your path (not another sccKit directory).
Edit /opt/sccKit/current/firmware/RockyLake/update/update.txt. You want a larger number. I often choose the date followed by an index … as in 20120106001 so that the least significant numbers increase earlier.
Run install.csh in /opt/sccKit/current/firmware.
Power cycle. Issue (providing the complete path) /opt/sccKit/current/bin/sccPowercycle –r
Initialize tith sccBmc –i.
Boot with sccBoot –l.
Check your FPGA bitstream with the following (this assumes you have either eMAC a or eMAC b enabled).

$ sccBmc -c set |grep FPGA

Default FPGA bitstream: /mnt/flash4/rl_20110624_ab.bit

Log onto a core and verify that you have the correct Linux kernel.

rck00:/root # uname -a

Linux rck00 3.1.4scc #4 SMP Wed Dec 21 14:41:27 CET 2011 i586 GNU/Linux

Message was edited by: Ted Kubaska: typo

The new SCC Linux is on Github

webadmin@intel.com — Wed, 21 Mar 2012 14:29:45 GMT

The latest SCC Linux is on github, not the public SVN that we've been using. Note that this SCC Linux works with sccKit 1.4.2 (now in beta), not sccKit 1.4.1.3. SCC Linux will build on a 1.4.1.3 system, and it will even boot; but the cores remain inaccessible. It's working fine on 1.4.2. You do not have to have a github account to build this Linux. If you want to fork sccLinux and issue a pull request, you must have a github account.

To build the 1.4.2 SCC Linux, issue the following commands:

# git clone git://github.com/hpi-scc/sccLinux
# cd sccLinux
# ./configure.sh
# cd buildroot-2011.11
# make sccDemo_defconfig
# make

sccKit14x_UsersGuide_Part8.pdf

webadmin@intel.com — Wed, 14 Mar 2012 21:35:12 GMT

SCC Platform Overview

webadmin@intel.com — Sat, 28 Jan 2012 00:45:47 GMT

SCCProgrammersGuide.pdf

webadmin@intel.com — Sat, 28 Jan 2012 00:35:42 GMT

RCCE Specification

webadmin@intel.com — Sat, 28 Jan 2012 00:24:51 GMT

Choosing the BusyBox Version Used by SCC Linux

webadmin@intel.com — Mon, 23 Jan 2012 23:48:46 GMT

We've had some questions about the BusyBox version that SCC Linux uses. Here is how you can change the Busybox version used by SCC Linux. When you are building SCC Linux, issue a "make menuconfig". Then, choose Package Selection for the target --> BusyBox Version (BusyBox 1.18.x) . You see a menu. With 1.4.1.3, the latest version is 1.18.x. You can also choose a daily snapshot. With 1.4.2, you can choose a 1.19.x as well as a daily snapshot.

And then of course you must rebuild SCC Linux. Please not that if you choose something other that 1.18.x, you are entering untested territory.