Posts

Showing posts from October, 2019

SOSP'19 Day 0

Image
I attended SOSP this week. SOSP is the premier conference on systems where 500+ researchers follow 30+ paper presentations in a single-track event over three days. SOSP is held every two years --on odd years, alternating with OSDI which is held on the even years.

This was my third SOSP. I had been to SOSP 2009 at Big Sky Montana and SOSP 2013 at Nemacolin Pennsylvania. It is always a treat to attend SOSP. I get to learn new ideas and meet with interesting people. SOSP never fails to impress me with the quality of papers and presentations. I attended almost all of the sessions on Monday and Tuesday and took a lot of notes. I will be releasing these notes over the next 4-5 posts as I find some free time to edit and post them. You can see the entire program here and download the papers freely as open access.

Today, I will just talk about day 0 and the opening of day 1.

Driving to SOSP Abutalib, a final year PhD student at CMU, had offered to give me a ride to the conference. At Buffalo, …

Book review. A Mind at Play: How Claude Shannon Invented the Information Age

This book was published by Jimmy Soni and Rob Goodman in 2017. It is 385 pages long and informative.

This is a good book. Shannon is already an extremely interesting researcher, so the book is interesting. The writing is good, gets very good at some places, but it is not top-class writing. A master storyteller like Michael Lewis ( e.g., "Undoing Project"), Walter Isaacson, or Steven Levy would have made this book excellent. I guess the difference would be that these masters would put in an order of magnitude more research in to the subject, do dozens of interviews, and extensive archive search. They would also distill the story and build the book around a single strong theme with some side themes tying to that, and tell a much more engaging story. They would not leave a stone unturned. They would go the extra mile to point us to the insights they gathered, without explicitly showing them, but gently nudging us toward them to make us think we came up with those insights.

Claud…

Recent book diet

The last couple of months I have been listening through books using the Libby app. I highly recommend the Libby app: It connects you to your public library, and let's you search, borrow, and download audiobooks from your library easily. I used to listen to a lot of podcasts, but after I downloaded Libby, I have been listening to books mostly. Here are some of those books I listened to.

The Science of Discworld III: Darwin's Watch (2005)This book is by Terry Pratchett, Ian Stewart and Jack Cohen. It is set on the Discworld world, and it teaches solid science while being entertaining at the same time. The book not only talked about evolution but also a lot about quantum physics, string theory and time travel (yes, the science behind time travel).

The book gives a good account of Darwin's life as well as his contemporaries, like Wallace. I think Darwin's superpower was writing. This was the Victorian era where suddenly the writers started to get and control mindshare of l…

Paper review: Comprehensive and efficient runtime checking in system software through watchdogs

Image
This paper by Chang Lou, Peng Huang, and Scott Smith appeared in HotOS 2019. The paper argues that system software needs intrinsic detectors that  monitor internally for subtle issues specific to a process. In particular, the paper advocates employing intrinsic watchdogs as detectors. Watchdogs (also known as grenade timers) have been widely used in embedded devices. Watchdogs use a decrementing timeout counter which resets the processor when it reaches zero. To prevent a reset, the software must keep restarting the watchdog counter after performing/clearing some sanity checks.


Table 1 summarizes the comparison of crash failure detectors, intrinsic watchdogs, and error handlers. Failure detectors are too general, they just make "up-or-down" decisions. They are only good for achieving liveness, as they are too unreliable for making safety decisions.

The disadvantage with error handlers, the paper argues, is  that liveness-related failures often do not have explicit error sign…

Book review: Three body problem

This book, by Cixin Liu, easily secures a place among the top 20 sci-fi books I have read. The book was 400 pages, but was very engaging. I felt sad when I found that I had finished book. I was happy again when I learned the book has two sequels. I am looking forward to reading the sequels.

The book started in a very engaging way with the discussion of cultural revolution. This was engaging for me because 1) I didn't know much about this period in Chinese history, and 2) I am an academic and I was aghast by what has been done to the academics and intellectuals at that period. I couldn't fathom such an ignorance was possible. But given the path Turkey has been going down during the past 10+ years, and given the descent of US politics to such a path, I  followed these descriptions in horror. I couldn't imagine things could get that bad and stay that bad that long.

The importance of basic science was very well emphasized in this book. The book had a meta message. It starts wi…

Frugal computing

Companies care about cheap computing.

Well, the first thing they care about is usability: Is it easy for average programmers to develop solutions using the framework?

And the second thing they care about is cheap computing: Does this break the bank? Can I do this cheaper?

Speed, efficiency, elegance, technical strength... These are often not of interest. People are OK with their analytic jobs return results hours later. We watched aghast, at the beginning of Hadoop epidemic, people use MapReduce for doing analytics in a wasteful and slow manner.

I was recently thinking about this question: How can we trade-off speed with monetary cost of computing? If the constraints are that the user will not need the results before a couple hours but it would be nice to get the results in a day, what is the cheapest way to get this analytics job done in the cloud?

While distributed systems may be the answer for a lot of questions (such as providing fault-tolerance, low-latency access for geo-distrib…

Popular posts from this blog

I have seen things

SOSP19 File Systems Unfit as Distributed Storage Backends: Lessons from 10 Years of Ceph Evolution

PigPaxos: Devouring the communication bottlenecks in distributed consensus

Frugal computing

Learning about distributed systems: where to start?

Fine-Grained Replicated State Machines for a Cluster Storage System

My Distributed Systems Seminar's reading list for Spring 2020

Cross-chain Deals and Adversarial Commerce

Book review. Tiny Habits (2020)

Zoom Distributed Systems Reading Group