Monday, August 12, 2013

Student Reports for ISCA 2013

I recently handled student travel grants for ISCA 2013.  As is customary, I asked awardees to send me a brief trip report:

"... explain what you saw at the conference that had a high impact on you.  This could be a keynote or talk that you thought was especially impressive, it could be a commentary on research areas that deserve more/less attention, on especially effective presentation methods, on ways to improve our conference/reviewing system, etc.  Please feel free to be creative..."

37 of the 68 awardees responded.  By most accounts, this was one of the most memorable ISCAs ever.  Several students highlighted the talk on DNA Computing.  Many also wished there was a session at the start with 90-second paper summaries (as was done at MICRO 2012).

Some of the more interesting comments (lightly edited and anonymized) are summarized below.

"... we have to leave the dream of hardware generality if we still want to increase performances with reasonable energy budgets.  I noticed a lot of work sitting between hardware specialized units and general purpose architectures. ... I really enjoyed the work presented by Arkaprava Basu in the big data session called Efficient Virtual Memory for Big Memory Servers.  The introductory quote in the paper reads: 'Virtual memory was invented in a time of scarcity.  Is it still a good idea?'  Experiments on widely used server applications show that many virtual memory features are not needed."

"I strongly recommend using the lightning session in future conferences."

"... Breadth of topics has been increasing over the years.  The paper on DNA computing was really, really good.  A tutorial or panel on emerging technology would also be very cool.  Potential list of topics: DNA/protein computation, quantum, resistive element storage & computing, bio-inspired computing and circuit technology, optical, circuits for near/sub threshold computing.

The split sessions were a bit off-putting.  I would also like all sessions to be recorded.

During the business meeting the idea of turning CAN into something like WDDD was brought up. I really like this idea.

I found Uri's discussion of memory-intensive architectures particularly compelling. I rather enjoy keynotes that present interesting, largely undeveloped research directions and ideas.  One thing that I thought was missing from this year's ISCA was a session on program characterization or application analysis. Given the amount of application- or workload- specific stuff we are seeing, this topic seems increasingly important. The release of data sets, benchmarks, and thorough analyses of application domains and workloads should not be relegated to ASPLOS/ISPASS -- I'd like to see them here at ISCA and encourage more of them. Especially in data center research (and to a lesser extent mobile) it seems like large companies have far more intuition and data on their workloads than is generally available to the community. Perhaps making a top-tier conference like ISCA a venue for that information would make the release of some (admittedly proprietary) information possible or attractive."

"I really enjoyed the panel in the Monday workshop that discussed the state of computer architecture in 15 years.  Similarly, I liked the second keynote on future directions and specifically the memristor."

"The talk by Gadi Haber in the AMAS-BT workshop was memorable.  In the talk, Gadi states that binary translation can be seen as an extension to micro-architecture. Things that are difficult in hardware are sometimes much easier to do in software. In fact, many groups are co-designing hardware with binary translators."

"Many talks/keynotes encouraged the use of cost as a metric for future evaluations.  I really enjoyed the session of emerging technologies, especially the DNA computing talk.  I also enjoyed the talk by Andreas Moshovos that had an entirely different way to pass the insight of their idea.

The most useful session for me was the data centers session.  Specifically, the last talk by Jason Mars was excellent and I really liked the insight that was provided for a large company like Google. Knowing that the studies mentioned in this work are important for a key player in the data center industry was reassuring.

One minor suggestion is to end the last day right after lunch to facilitate travel."

"I especially enjoyed the talk on ZSim. I think simulators should be a more discussed area in computer architecture research.

One thing I would suggest is that the keynotes should be more technically informative. I thought the first keynote contained more personal opinions than technical reasons.

Another thing I would suggest is that all speakers should be required to present their paper in 2-3 mins at the very start of the conference."

"I especially enjoyed the 'Roadmaps in Computer Architecture' workshop."

"The thing that had the most impact on me was the chats I had with stalwarts of computing in the hallway. ... I think the idea of lightning talks like that in MICRO 2012 would have been really helpful."

"The two keynotes were very complementary.  One looked back at history and the other was very inspiring for future research directions.  The most impressive paper presentation was on the Zsim simulator.  The author ran the power point on their simulator with dynamically updated performance stats.  I would also suggest recording all presentations."

"I followed with interest the opening keynote by Dr. Dileep Bhandarkar.  For a newbie, it's really nice to listen to the history of computer evolution.  Another interesting presentation was on the ZSim simulator.  It was very funny to see the thousand core systems simulator up and running during the presentation itself.  The presenter precisely and clearly explained how choices were made to get the maximum performance."

"Among the talks I attended, the ideas that mostly intrigued me were Intel's Triggered Instructions work (Parashar et al.), and the introduction of palloc as an approach toward moving energy management control for datacenters to the software level, similar to the use of malloc for memory management (Wang et al.). I also found the thread scheduling work on asymmetric CMPs very interesting (Joao et al.).

... some presentations also had obvious flaws on the static part, i.e., the slides - full sentences, no smooth transitions between slides, overloaded content.  Maybe an improvement could be achieved by imposing some rules (the same way as rules are set for paper submissions), or by organizing a tutorial session during the conference where 'Giving a good presentation' would be taught.

I thought that the time dedicated for Q&A after each presentation was quite limited.  One thing I could think of is having (additional) Q&A time for each set of papers rather than each single paper, so that the dedicated time can be filled up according to the audience's interest for each of that set's papers."

"I'd like to see a poster session in future ISCA editions, e.g., including papers that didn't make it to the main conference."

"I have been interested in taking security research further down the hardware software stack, but it appears as though most security research at ISCA is focused on things such as side channel attacks. I think that one interesting area is to look at security accelerators or security mechanisms in hardware that increase either performance of common security solutions or improve security of said solutions. Security co-processors, as I observed in a few of the talks, do not solve primary security issues, and the problems need to be tackled at more fundamental levels."

"The most impressive talk for me was by Richard Muscat, 'DNA-based Molecular Architecture with Spatially Localized Components'. I was truly amazed when he reached a specific slide that explains how he managed to use DNA molecules as a wire to transmit the result of a computation and, therefore, enabling composition of many modules of DNA computation, while the previous approach to DNA computing is limited to doing a single computation in a soup of DNA. This is a huge step towards enabling intelligent drugs that implement some logic by using DNA molecules.  I also especially appreciated the last two talks about program debugging ('QuickRec: Prototyping an Intel Architecture Extension for Record and Replay of Multithreaded Programs' and 'Non-Race Concurrency Bug Detection Through Order-Sensitive Critical Sections'). They offer interesting insights on how to enable better debugging of parallel programs, which currently is very frustrating to do. I hope that in the near future we have better options to efficiently debug parallel software instead of having to stick to 'errorless programming' :) "

"I want to emphasize the 'Emerging Technologies' session (Session 3A) and especially the work about DNA-based circuits by Richard A.  Muscat et al. I have to admit that I was not really aware of the fact that there is that much research going on in the field of DNA, which might also be of interest for the computer architecture community. Nevertheless, especially in a time where we discuss whether Moore's law may not hold any more in the near future (as it was also a topic throughout the keynotes at ISCA'40), I think that investigating all kinds of alternative ways to construct "logic circuits" must be paid high attention. Assembling such circuits based on a modular approach using DNA structures may sound like a science fiction movie these days (at least for myself at the moment), but who imagined a few decades ago that we are going to run around in public, wearing camera- and other high-tech-equipped glasses? So although it does not fall into my research area at all, please keep up that great work!

One of the authors presenting a workshop paper was not able to attend.  Therefore, they prepared a screen-captured video presentation. Basically, I am not really a fan of such presentation methods, but then I was positively amazed because they really did a great job and presented their work very well. However, I think in general and especially for a large audience (like the main symposium of ISCA), physically present speakers should be favored in the future ('discussions' with a laptop and a projector are somehow difficult :)."

"The session with the highest impact on me was 'Emerging Technologies'.  The proposals regarding quantum computers and DNA-based molecular architecture provided an insight about how computing will be in the next years. Thus, in my opinion similar type of works should be supported."

"The most interesting part was the keynote given by Prof. Uri Weiser. He talked about heterogeneous and memory intensive architecture as the next frontier.  I think ISCA may need more such talks about future technology."

"There are three highlights that come to mind: the keynote by Dr. Dileep Bhandarkar, the presentation of 'Thin Servers with Smart Pipes: Designing SoC Accelerators for Memcached', and the Workshop on Energy Efficient Design.

Keynote: ... Dr. Bhandarkar's advice to 'wear many hats' , 'you don't grow until you step out of your comfort zone', 'don't be encumbered by past history', and statement that 'strategy without execution is doomed' are particularly noteworthy. Dr. Bhandarkar's anecdote concerning the development of Itanium was also illustrative, I was previously aware of the external controversy over the architecture but did not know of the degree to which Intel sought to protect Itanium from internal competitors. Additionally, Dr. Bhandarkar's assertion that destabilizing technologies come from below (cheaper, lower powered, efficiency vs. performance) was certainly thought provoking. Finally,  Dr. Bhandarkar's demonstration of the complexities of Qualcomm's snapdragon system architecture and assertion that DSP's will require new levels of programmability during the question session was intriguing.

Thin Servers: I enjoyed the presentation and had higher than average insight into this topic as my background is in networking. Briefly, I was intrigued with the custom platform developed to speed lookups, I thought the performance analysis was well done. A drawback of the work was the lack of evaluation vs. NetFPGA solutions, but the presenter claimed that their SoC solution was more compliant with the existing memcached protocol. At a high level, I think it is an interesting counterpoint to Dr. Bhandarkar's assertion that increasing programmability is necessary. It would seem that flexible, low cost development and fabrication platforms are also extremely important to developing heterogeneous systems.

WEED: I found the discussion session led by Karthick Rajamani at the end of the workshop to be thought provoking. Especially his comments pointing to increasing interest in the power consumption and control of memory systems.  Additionally, I appreciated his efforts to show the impact that past workshop papers had via follow up papers at conferences."

"The opening keynote by Dr. Bhandarkar was very interesting. ... I really liked the fact that the security session and the reliability session were scheduled back to back as they often share similar audiences. I would recommend such scheduling in the future."

"I would like to comment on the Emerging Technologies Session. I feel it was too much introduction and too little presentation of what was done in the research. I propose to double time for this session. First part should be introduction, for those who are not aware of those technologies, and second part should be deep analysis of the work done by the authors."

"I thoroughly enjoyed the Accelerators and Emerging Architectures session for their creativities in facing the dark silicon and utilization wall problems head on. I also was particularly interested in the Big Data session as this is my research direction and I believe the architecture community is and should be focusing on this area. I regret that I was not able to attend the Power and Energy session as it was put in the session parallel with the Big Data session; I believe solving power and energy problems is imperative in all aspects of hardware architecture/design.  I enjoyed Uri's keynote on heterogeneous and memory intensive architecture.  I generally agree with his take on the future of computing being heterogeneous and memory intensive, however, I am not sold on the applicability and feasibility of the proposed MultiAmdahl law just yet.  I think more research on heterogeneous and memory intensive architectures would help the community."

"The most impressive talk was DNA-based Molecular Architecture with Spatially Localized Components. It is amazing how computer architecture evolved in the last 40 years, but the ability of computing using DNA sequences is something beyond extraordinary. New secure hardware methods to prevent rootkit evasion and infection were also pretty interesting, I would like to see more talks on security in the future.  Besides the technical part, the fact the conference was held in Tel Aviv gave an exotic personality to the event. The dinner with the 'Jerusalem Old City Wall' sightseeing, followed by an exciting drum experience, really promoted a smooth integration between the participants."

"I found two things to be quite inspiring at ISCA.  The first was the initial keynote at the conference.  Dr. Bhandarkar's talk drove home the fact that a lot of innovation in our field is indeed driven by these disruptive shifts to smaller, more pervasive form factors.  I have always been a fan of the history of computers, but it was great to see how one person could touch on so many significant paths through that trajectory over a career.  The second was a paper from the University of Washington on DNA-based computing.  While it may not be the next disruptive change, it's always important to keep perspective on how we can apply technology from our field to other areas, as it opens up doors that we never even thought of before.  I hope that future conferences continue to have such diverse publications, in order to encourage others in our field to also think outside the box."

"When I talked with fellow students at the conference, the ideas that amazed me most were actually from the session parallel with the one in which I presented: I really like the ideas in online malware detection with performance counters, as well as the notion of a provable totally secure memory system.  Now that we have parallel sessions, ISCA could also do something like 3-min highlights for each paper, or a poster session for all papers.  It's really a pity to miss something in the parallel session!"

"I really enjoyed ISCA this year, particularly because of the broader range of research areas represented. I found the sessions on Big Data and Datacenters a great addition to the more traditional ISCA material.  I also liked Power and Energy and Heterogeneity.  I would love to see ISCA continue to take a broader definition of computer architecture research in the upcoming conferences.  Additionally, the presentations themselves were extremely high quality this year.

However, I think the 25 minute talk slot was not long enough.  Most talks had time for only one question, which is ridiculous. Part of the value of attending the conference rather than just reading the paper is to interact with the other researchers.  However, often when an industry person (such as from Google or Microsoft) with some useful insight to add was not allowed to speak.   Either the sessions should be lengthened or the talks should be shortened, but there should definitely be more Q & A time."

"Firstly, this was the nicest conference I've attended thus far in my graduate studies (out of previous ISCAs and others). The venue was in a very beautiful location, the excursion was educational and quite fun, the conference itself was very well organized, and I felt that the quality of papers this year was strong. Although I probably can't say that I fully understood each paper in this session, I thought that the Emerging Technologies session this year was very interesting; especially the paper 'DNA-based Molecular Architecture with Spatially Localized Components'.  This area of research is quite different than my current focus on GPGPU architectures, but I found it very intriguing to see how they were using DNA strands to create very basic digital logic structures. As this research seems to be in its infancy, I'd be interested to see where this research goes in the future and how it's applicability to the human body evolves.  Commenting on one of the especially effective presentation methods, I thought that "ZSim: Fast and Accurate Microarchitectural Simulation of Thousand-Core Systems" was presented very well. The presenter, Daniel Sanchez, was actually running the entire power point presentation through their simulation framework, showing various statistics at the bottom of the screen during the talk. I thought that this was a very cool way of highlighting the speed and applicability of such a simulator while presenting the detailed implementation in the talk."

"I'll focus my comments on the Roadmap Workshop, which was the highlight of the conference for me.  The talks I attended focused on where technology would be a decade from now. Doug Burger was of the opinion that the cell phone would become the primary device for all personal computation. Devices will collect large amounts of data about users and use that data to predict things like the user's health. The cloud would be split into two parts, a personal cloud running out of the user's home and the cloud that lives in large data centers.  Privacy would be a major issue, hence all of the users' personal information would lie in the personal cloud, while anonymized data would be uploaded into the cloud. The large hordes of data in the data center cloud in combination with the personal cloud would be used to identify patterns and predict events (health related) in the life of the user.  Devices would rely more on non-standard modes of input like gestures (kinect) and touch.  Personal assistant applications would become more intelligent and be able to do more that just maintain calendars. In conclusion, devices would become smarter than humans in a large variety of tasks, helped by their ability to parse through huge amounts of data.  I thought this was one of the best talks at this year's ISCA.

Other talks focused more on the end of Dennard scaling. The speakers were of the opinion that Moore's law would continue for a few more generations, but Dennard scaling was at an end because voltage no longer scales with smaller technology nodes. More exotic, one-off technologies would be used in the future. Though many believe that the only way to scale going forward is with the introduction of Dark Silicon, most speakers believed that Dark silicon was economically infeasible. Instead, dim silicon was believed to be the solution."

"I found ISCA to be well organized and with a solid technical program.  Almost all presentations I attended were interesting contributions, although I was not particularly shocked by any of them as to highlight it. So, I want to focus on the issue of where to organize ISCA abroad.  Personally, I enjoyed ISCA being in Israel probably more than if it had been in any other place in the world, in good part due to the possibility of touring Jerusalem. However, I found it troubling that many people from US companies and universities that usually attend ISCA did not make it to Tel-Aviv. Cost may have been an issue (especially for students, even after factoring in the travel grant), distance/time zones may have also been an issue. Maybe even the perceived safety risks of being in Israel? Maybe this was my own personal perception and I may be wrong about it (I had not attended ISCA since 2009). I don't know how attendance numbers compare to previous ISCAs, but it would be interesting to poll regular ISCA attendees in our community to ask them why they did not go, and then consider that input for the decision about where to organize future ISCAs. Anyway, I understand the trade-offs of organizing ISCA abroad and I know it's hard to pick a place that is both interesting and easy to travel to from the US and from Europe, and that also has a team of local people in the community who can do a good job organizing it."

"I think my experience at ISCA was different from that of most of the attendees because I'm a fresh grad student in the area of quantum computing.  A talk that really impressed me was the DNA Computing talk. One of the challenges in presenting an emerging architecture to a general audience is providing enough background to make the topic accessible. The speaker was able to present the material in a way that gave me a good understanding of the challenges and innovations in DNA computing in 20 minutes without getting bogged down in details."

"I particularly liked the emerging technology session. Those are wild yet reasonable and well-developed ideas. Another paper I liked is the convolution engine one from Stanford. It has a clear motivation and convincing solution, as well as rich data that not only supports their own work, but also gives me good intuition on energy consumption distribution in modern processors. I also benefited a lot from the DRAM session."

"For future ISCAs, I would like to see the conference scope slightly extended such that application specialists can find their place in the conference.  Application are a driving factor in the development of new systems.  While PPoPP and HPCA are co-located, there is considerably little interaction between these two communities even though their interests overlap."