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Reflecting on CS Graduate Admissions

I was just indulging in my favorite bad habit (reading hacker news), when I came across a discussion about  prestige in faculty hiring  - namely, the fact that the majority of CS professors across the US come from the top 18 or so universities, and that even within that, there's bias.  The HN discussion turned to Ph.D. admissions, with a commenter noting: " I'm not sure, but I'd bet that the best institutions actually don't care where their applicants come from. They can afford to just choose the best. It's the so-so places that have to signal their quality by 'hiring the best'. I've seen this in graduate school applications - students with poor marks often stand a better chance of admittance in a top program than a so-so one. " I just finished chairing the CMU CS Ph.D. admissions committee, so I thought it might be worth writing down my experience in doing so.  With two very important notes: I'm not doing it next year, so please don...
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Chili Crisp Showdown: Laoganma and Flybyjing

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I've been on a bit of a chili crisp mission lately.  The Internets -- and my friends -- appear convinced that the best chili crisp is Laoganma .  Or Flybyjing .  Certainly one of them.  But which? My answer, alas, is that you might want a bottle of each.  Or five bottles of each.  Let's jump in: Laoganma on the left, Flybyjing on the right.  The famous slightly disapproving face of the old grandmother stares at us, contrasted with the apparently very-hard-to-print rainbow label of the newer entrant.  Opening up the containers, one is immediately struck by the color and texture differences: Laoganma, on the left in both photos, has more "crunchy bits", but also has fewer suspended solids in the oil.  The bottle is about 3/4 full of the solid crispy bits.  The flybyjing bottle is only about 1/3 full of crispy bits. This difference flows through to the spoonfuls below -- much more crispy stuff in the laoganma, but its oil...
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Caring about Causality - now in Cassandra

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Over the past few years, we've spent a bunch of time thinking about and designing scalable systems that provide causally-consistent wide-area replication.  (Here, "we" means the team of Wyatt Lloyd, Michael Freedman, Michael Kaminsky, and myself;  but if you know academia, you wouldn't be surprised that about 90% of the project was accomplished by Wyatt, who's a graduating Ph.D. student at the time of this writing.)  I'm posting this because we've finally entered the realm of the practical, with the release of both the paper  (to appear at NSDI'13) and code for our new implementation of causally-consistent replication (we call it Eiger) within the popular Cassandra key-value store. Why do we care about consistency in wide-area replication? Because there's a fundamental, unavoidable trade-off between having guaranteed low-latency access (meaning not having to send packets back-and-forth across the country) and making sure that every client sees ...
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