Reducing the Memory Footprint of Parallel Applications with KSM
In the era of multicore and manycore programming, memory represents a restrictive resource and it is therefore necessary to share as much as possible between processes. But in many cases, in which a parallel execution of an application has never been foreseen, it is difficult to apply a shared memory model afterwards. The KSM-tool (Kernel Same Page Merging) provides an easy ad-hoc-solution to reduce the overall memory footprint. This paper shows that in the applications of the LHCb experiment at CERN between 8% and 48 % of memory can be gained. In addition it will be discussed how to adjust KSM in order to balance the gain in memory and the additional CPU consumption.
KeywordsVirtual Machine Work Process Parallel Application Memory Footprint LHCb Experiment
Unable to display preview. Download preview PDF.
- 1.Linux @ cern (2012), http://linux.web.cern.ch/linux/scientific6/
- 2.Wlcg worldwide lhc computing grid (2012), http://wlcg.web.cern.ch/
- 3.Alef, M.: Cpu benchmarking at gridka (2012), http://indico.cern.ch/getFile.py/access?contribId=40&sessionId=2&resId=0&materialId=slides&confId=160737
- 4.Arcangeli, A., Eidus, I., Wright, C.: Increasing memory density by using KSM. In: OLS 2009: Proceedings of the Linux Symposium, pp. 19–28 (July 2009)Google Scholar
- 6.Belyaev, I., Charpentier, P., Easo, S., Mato, P., Palacios, J., Pokorski, W., Ranjard, F., Van Tilburg, J.: Simulation application for the lhcb experiment. Technical Report physics/0306035, CERN, Geneva (June 2003)Google Scholar
- 9.Chang, C.-R., Wu, J.-J., Liu, P.: An empirical study on memory sharing of virtual machines for server consolidation. In: 2011 IEEE 9th International Symposium on Parallel and Distributed Processing with Applications (ISPA), pp. 244–249 (May 2011)Google Scholar
- 10.Corbet, J.: Transparent hugepages (2009), https://lwn.net/Articles/359158/
- 12.Kerrisk, M.: Linux programmer’s manual (2012), http://man7.org/linux/man-pages/man2/madvise.2.html
- 13.Yagi, T., Artho, C., Suzaki, K., Iijima, K.: Effects of memory randomization, sanitization and page cache on memory deduplication. In: European Workshop on System Security, EuroSec 2012 (2012)Google Scholar
- 16.Suzaki, K., Yagi, T., Iijima, K., Quynh, N.A., Artho, C., Watanebe, Y.: Moving from logical sharing of guest os to physical sharing of deduplication on virtual machine. In: Proceedings of the 5th USENIX Conference on Hot Topics in Security, HotSec 2010, pp. 1–7. USENIX Association, Berkeley (2010)Google Scholar