My Current Work:
I am working on energy management in servers - primarily on the
ability to actively manage energy consumption.
- Trending and control of energy consumption in servers
- Save energy through both fine grain and coarse grain consolidation
Right now I am working on primarily platform-level capabilities, but
I am also working with a number of people to improve utilization
of resources that consume power (CPU, memory, I/O) in future systems.
Some of the initial discussions around these happened at
Ottawa Linux Symposium 2008 -
Power Management Summit. At the moment, we are pushing towards
efficienty consolidating work into small number CPU packages
through scheduer changes and letting other packages go to deep
sleep longer.
My Linux kernel patches can be found here.
Many of those patches are in mainline now, so they are just a historical
reference. I intend to upload lot of the experimental versions
of my earlier work - specially various Read-Copy Update implementations
there. Hopefully, as soon as I get time to sort to piles of old patches.
My Earlier Works:
I did most of the original Read-Copy Update synchronization
primitive deveopment work in Linux between 2001 and 2004 along
with Paul McKenney. It was included in the mainline Linux
kernel in 2003 and subsequently I worked on using RCU
to scale some of the cache lookups in the Linux kernel.
Some of my earlier work from a couple of years ago are -
Lock-free
file descriptor management patchset which is a rewrite of
how we maintain the information about open files of a task
in the Linux kernel. The new model keeps file information in a separate
fdtable structure which is replaced by a new one when
file information expands beyond its capacity. This allows
atomic update and there by use RCU for lock-free look-up
of file information. This eliminates the current overhead
that posix threads incur (by sharing the file descriptor
table and bouncing its lock cache line) on I/O compared to processes.
My current publications:
- V. Srinivasan, D. Sarma, V. Srivatsa, G. Shenoy, S. Siddha
Energy aware task and interrupt management,
Proceedings of Ottawa Linux Symposium, Ottawa, July 2008.
pdf
- P. McKenney, I. Molnar, S. Bhattacharya, D. Sarma,
Extending RCU for Realtime and Embedded Workloads,
Proceedings of Ottawa Linux Symposium, Ottawa, July 2006.
pdf
- Ravikiran Thirumalai, Dipankar Sarma, Manfred Spraul,
Ho Hum, Do We Need Another Dynamic Per-CPU Allocator ?,
Proceedings of Ottawa Linux Symposium, Ottawa, July 2005.
pdf
- Paul E. McKenney and Dipankar Sarma,
Towards Hard Realtime Response from the Linux Kernel,
Proceedings of Linux.conf.au, Canberra, April 2005.
pdf
- Dipankar Sarma and Paul E. McKenney,
Issues with Selected Scalability Features of the 2.6 Kernel,
Proceedings of Ottawa Linux Symposium, Ottawa, July 2004.
pdf
- Dipankar Sarma and Paul E. McKenney, Making RCU Safe for
Deep Sub-Millisecond Response Realtime Applications,
USENIX, Boston, June 2004.
pdf
- Andrea Arcangeli, Mingming Cao, Paul E. McKenney
and Dipankar Sarma,
Using Read-Copy-Update Techniques for System V IPC in the
Linux 2.5 Kernel, USENIX, San Antonio, June 2003.
pdf
- Paul E. McKenney, Dipankar Sarma, Andrea Arcangeli, Andi Kleen,
Orran Krieger, Rusty Russell,
Read Copy Update , Proceedings of Ottawa Linux Symposium,
Ottawa, June 2002. pdf
- Hanna Linder, Dipankar Sarma and Maneesh Soni,
Scalability of the Directory Entry Cache,
Proceedings of Ottawa Linux Symposium, Ottawa, June 2002.
pdf
- Paul E. McKenney, Jonathan Appavoo, Andi Kleen,
Orran Krieger, Rusty Russell, Dipankar Sarma and Maneesh Soni,
Read-Copy Update, Proceedings of Ottawa Linux Symposium, Ottawa,
July 2001. pdf
My Other Interests:
Disclaimer:
Opinions here are solely mine and not necessarily of my employer.