Feature List

Zepto Compute Node Linux

Optimized kernel based on Linux 2.6.19.2 runs on the compute nodes of Blue Gene/P, with a slim ramdisk less than 1/3 of the size of the default I/O-node one.

Zepto-enhanced I/O node Linux

Our I/O node kernel and ramdisk are based on the standard V1R3M0 release, but feature a number of ZeptoOS-specific improvements.

Run arbitrary processes on the compute nodes

Shell scripts, Java VM, unrestricted pthreads, etc.

Big Memory support

Zepto Compute Binaries run in Big Memory, a flat memory area covered by huge, semi-static TLB entries, resulting in a run-time performance comparable to that of a light-weight kernel.

Native communication support

The DMA driver, as well as standard BG/P communication libraries, such as MPICH2 and the lower-level DCMF and SPI have been ported to the Zepto Compute Node Linux, providing the applications with communication performance matching that of the light-weight kernel. Currently only the SMP mode is supported.

ZOID

ZeptoOS I/O Daemon performs job control and enables communication (remote file I/O, etc) between the compute nodes and the I/O nodes. ZOID can be easily extended through plug-ins to perform the forwarding of custom APIs.

Log into your I/O nodes

SSH daemon is enabled by default and is configured to allow the partition owner to log on the I/O nodes while the job is running.

Log into your compute nodes

Once logged on an I/O node, a user can open an interactive session to a compute node using telnet in order to, e.g., attach gdb to an application process running there. This is made possible using the IP packet forwarding over the tree network, performed by ZOID.

PVFS Support

Pre-built binaries of PVFS client code version 2.8.1, including the I/O node kernel module, are included in the ZeptoOS tarball for your convenience.

ALL Source Code

The ZeptoOS tarball includes all the source code: kernels, ramdisks, communication libraries, I/O forwarding, support libraries, tools and utilities, etc, along with all the support scripts and Makefiles needed to build binaries out of them. Pre-built binaries are also included for your convenience.