Another Improvement in Hard Drive Densities

November 28th, 2010

At SC10 last week someone asserted that hard drives were a dead technology, and that attempting to improve the performance of spinning disks access was a waste of time. Galen was with me and together we pointed out that hard drives are going to be with us for the foreseeable future.

The belief that the end of disk density improvements is imminent comes up over and over with people who do not work in the storage area — but I’m here to tell you that HDD research and development is still occurring at a staggering rate. In the last several years, the rate of improvement for disk density has been increasing rather than decreasing. Perpendicular recording was a big deal. Sticking the bits on their end took us to 3TB of storage in 3.5″ drives.

Currently we are looking forward to three more improvements: patterned media, heat assisted magnetic recording, and shingling. And patterned media looks to be available soon. From the article we can expect this technology to drive our disks over the 10TB capacity level — which is a staggering amount of storage. With a little hand waving and projection its not hard to imagine HAMR and shingling to drive disk capacities close to 100TB. If we estimate half that for a 2.5″ drive, it still only takes 20 such drives to construct a Petabyte file system! All of these technologies are likely to be available at the time of Exascale machine construction, so I expect that hard disk drives are likely to play a significant role in the construction of Exascale storage systems — though I also expect other storage media (e.g. storage-class memory) will also be a significant element of future extreme storage systems.

A Study of Client-based Caching for Parallel I/O

August 30th, 2009

Bradley W. Settlemyer.
“A Study of Client-based Caching for Parallel I/O.” [pdf]
Clemson University Doctoral Dissertation, Aug 2009.
Read the rest of this entry »

Greatest Novels – The Grapes of Wrath

July 14th, 2009

The Grapes of Wrath by John Steinbeck (10)

Mainly about the human condition, but centered around the story of Tom Joad and family traveling in the great migration to California. Steinbeck didn’t mince words, or strive for subtlety, this is an overt plea against capitalism for communism (if you want critics to love your book, champion communism, the critics are suckers for it every time). It’s very long, and surprisingly difficult to finish, it reminds me very much of Uncle Tom’s Cabin. To my mind, its inferior to his later The Winter of Our Discontent in almost every respect, but I must admit that the themes are much more accessible and overt in this novel, while Winter is perhaps a bit challenging (though not nearly as long).

[Originally written June 26, 2002.]

Book Report – Mrs. Frisby and the Rats of NIMH

July 7th, 2009

Mrs. Frisby and the Rats of NIMH by by Robert C. O’Brien.

Although I loved this movie as a child (I even had the storybook), I never read the real book. Huge mistake, this book was fantastic. The movie and novel depart significantly, with there being no magical component to the novel at all. Which is a good thing, as the book is even more compelling and interesting without it. The story starts with Mrs. Frisby, a mouse, who has recently become a widow and whose young son is sick. Although her son’s condition is improving, he is too sick to move, and the mouse family must move because their house will be destroyed by the farmer in five days. This problem eventually leads her to contact the rats of NIMH, a set of genetically modified super rats. Unlike the movie, the intrigue is not a power struggle within the rat community. That problem is resolved before the time of the book. Instead, the focus is on the rats starting a new rat-centric society to rival the human society that created the rats and that the rats depend upon for sustenance. During all of this we meet the kind crow, Jeremy; the formidable cat, Dragon; and the wise Great Owl.

Did I mention this book was great? I loved it. It actually reminds me of the great juvenile novels I read in my youth (Charlotte’s web, The Fantastic Henry Sugar, The Hobbit). Maybe I should track down some of those and enjoy those again as well.

Book Report – Watchmen

July 7th, 2009

Watchmen by Alan Moore.

I did not get a chance to watch the Watchmen movie due to budgetary and time constraints, so this review is of the bound comic book series only. I am not a huge fan. I grew up on and loved the comic books of the 1980s, but I guess maybe I’m too much of a Marvel guy. In my opinion Watchmen dragged on without enough action or intrigue to sustain my interest. I appreciate the elements of mystery, but there are some serious problems with even following the story. Consider, the mystery is over the death of the Comedian — a character we have never met and don’t like at all from the beginning. The death is investigated by Rorschach, who I liked and wanted to learn more about, but instead we mainly get back story on the other superheroes in town. A boring lot for the most part. By the time we finally get around to learning what I originally wanted to know about Rorschach, the plot has shifted to the disillusionment of Dr. Manhattan — a character I found mostly uninteresting. I do have to credit the ending. I wasn’t happy with the outcome, but I did think it was a good critique of the unsophisticated moralizing of most comic book characters.

From a craftsmanship approach I don’t understand why they didn’t simply set the book in London. The portrait of New York in the 80s was not accurate. Write what you know instead of pretending you know what you don’t. Alan Moore is British, and should probably stick to writing about Britain if he isn’t going to travel to the US and at least get his portrait somewhat correct.

Greatest Novels – The Great Gatsby

July 6th, 2009

The Great Gatsby by F. Scott Fitzgerald (2)

A book about the American dream, new rich versus old rich, and the notion of success. A very good book, but perhaps a bit overrated. The lyrical style is very impressive, and I commend its brevity, but really at the end of the novel, are you anywhere different than when you began. The achievement seems to me to be the tightness of the story told, which is fortunate, since the out of order story telling sometimes makes it difficult to figure out what has happened. Though Gatsby is certainly very good, I don’t find it greatly superior to, say, To Kill a Mockingbird, which is perhaps not as lyrically impressive, but an excellent example of this style of novel, nevertheless.

[Originally written June 12, 2002]

Greatest Novels – Catch-22

June 29th, 2009

Catch-22 by Joseph Heller (7)

A humorous tale about the paradox of war and the desire for survival, that also manages to examine the violence and madness of conflict. Uses the popular technique of out of order story telling, and mixes in rapid fire, scatterbrained dialog sequences that are fun to read and humorous, but eventually drag on over the novel’s length. Though the length seems obsessive, the end is climactic, and some of the paradoxes of war are driven home. This is definitely one of the greatest books I’ve read, and though the length and excessive vocabulary is a bit tedious, the novel really is a masterpiece.

[Originally written June 16, 2002.]

A Mechanism for Scalable Redundancy in Parallel File Systems

June 24th, 2009

Bradley W. Settlemyer.
“A Mechanism for Scalable Redundancy in Parallel File Systems.” [pdf]
Clemson University Master’s Thesis, May 2006.
Read the rest of this entry »

Using Server to Server Communication in Parallel File Systems to Simplify Consistency and Improve Performance

June 24th, 2009

Philip H. Carns, Bradley W. Settlemyer, and Water B. Ligon, III.
“Using Server to Server Communication in Parallel File Systems to Simplify Consistency and Improve Performance.” [pdf]
In The International Conference for High Performance Computing, Networking, Storage, and Analysis (SC ’08).
[21% acceptance, 59/277]
Read the rest of this entry »

C++ Syntax Highlighting for GNU Emacs/XEmacs

June 23rd, 2009

Several years ago the C++ syntax highlighting support in Emacs was pretty terrible.  The XEmacs support was particularly atrocious (and still may be).  To remedy that, I wrote my own syntax highlighting package for XEmacs originally, and then I ported it to GNU Emacs.  Back then I cared a lot more about the schism between XEmacs and Gnu Emacs.  Writing this package is one of the major impetuses for getting me to care a whole lot less about the politics of free software.

Read the rest of this entry »