Recent Trends in Memory Technologies and OS

Pradeeban Kathiravelu

INESC-ID LisboaInstituto Superior Tecnico, Universidade de Lisboa

Lisbon, Portugal

Modern Operating System Kernels – Presentation 2.April 27, 2015.

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NVM+DRAM

DRAM and Future..

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NVM+DRAM

DRAM + Non-Volatile Memory (NVM) = WIN!

Why not just replace DRAM with Flash?

+++ of Flash

Less cost/bit.Less power consuming.Less space consuming.

— of Flash

Erase before Write. Erase blocks; not just words.Less endurance. Die fast in the writing speed of the main memory.Slow write.Read timing - NAND flash reads entire page. NOR flash similar toDRAM (though at lower bandwidths).

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Hare

What is an Operating System?

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Hare

What is an Operating System?

Figure : What Defines a Computer Operating System?1

1http://www.explainxkcd.com/wiki/index.php/1508:_Operating_SystemsPradeeban Kathiravelu (IST-ULisboa) NSOM 5 / 8

Hare

What is an Operating System? [2]

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Hare

Portable Operating System Interface (POSIX)

Fully or Mostly POSIX-Compliant Operating Systems

IBM AIX.

Integrity.

Solaris, OpenSolaris, ..

OS X Yosemite.

BeOS, Haiku, ..

FreeBSD, OpenBSD, NetBSD, ..

Most Linux Distributions.

MINIX.

. . .

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Hare

Hare File System for Non-Cache-Coherent Multicores

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Hare

References

Mogul, J. C., Argollo, E., Shah, M. A., & Faraboschi, P. (2009, May).Operating System Support for NVM+ DRAM Hybrid Main Memory.In HotOS.

Gruenwald III, C., Sironi, F., Kaashoek, M. F., & Zeldovich, N. (2015,April). Hare: a file system for non-cache-coherent multicores. InProceedings of the Tenth European Conference on Computer Systems(p. 30). ACM.

Silberschatz, A., Galvin, P. B., Gagne, G., & Silberschatz, A. (1998).Operating system concepts (Vol. 4). Reading: Addison-Wesley.

Roman, M., Hess, C., Cerqueira, R., Ranganathan, A., Campbell, R.H., & Nahrstedt, K. (2002). A middleware infrastructure for activespaces. IEEE pervasive computing, 1(4), 74-83.

Thank you!Pradeeban Kathiravelu (IST-ULisboa) NSOM 9 / 8