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1. Scale-dependent halo bias from scale-dependent growth

   https://doi.org/10.1103/PhysRevD.83.063511  

   Parfrey, Kyle ; Hui, Lam ; Sheth, Ravi K. ( March 2011 , Physical Review D)
2. RackSched: A Microsecond-Scale Scheduler for Rack-Scale Computers

   Zhu, Hang ; Kaffes, Kostis ; Chen, Zixu ; Liu, Zhenming ; Kozyrakis, Christos ; Stoica, Ion ; Jin, Xin ( November 2020 , 14th USENIX Symposium on Operating Systems Design and Implementation)

   null (Ed.)

   Low-latency online services have strict Service Level Objectives (SLOs) that require datacenter systems to support high throughput at microsecond-scale tail latency. Dataplane operating systems have been designed to scale up multi-core servers with minimal overhead for such SLOs. However, as application demands continue to increase, scaling up is not enough, and serving larger demands requires these systems to scale out to multiple servers in a rack. We present RackSched, the first rack-level microsecond-scale scheduler that provides the abstraction of a rack-scale computer (i.e., a huge server with hundreds to thousands of cores) to an external service with network-system co-design. The core of RackSched is a two-layer scheduling framework that integrates inter-server scheduling in the top-of-rack (ToR) switch with intra-server scheduling in each server. We use a combination of analytical results and simulations to show that it provides near-optimal performance as centralized scheduling policies, and is robust for both low-dispersion and high-dispersion workloads. We design a custom switch data plane for the inter-server scheduler, which realizes power-of-k- choices, ensures request affinity, and tracks server loads accurately and efficiently. We implement a RackSched prototype on a cluster of commodity servers connected by a Barefoot Tofino switch. End-to-end experiments on a twelve-server testbed show that RackSched improves the throughput by up to 1.44x, and scales out the throughput near linearly, while maintaining the same tail latency as one server until the system is saturated. 

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3. RackSched: A Microsecond-Scale Scheduler for Rack-Scale Computers

   Zhu, Hang ; Kaffes, Kostis ; Chen, Zixu ; Liu, Zhenming ; Kozyrakis, Christos ; Stoica, Ion ( January 2021 , OSDI 2021)

   null (Ed.)
4. Bridging molecular-scale interfacial science with continuum-scale models

   https://doi.org/10.1038/s41467-024-49598-y  

   Ilgen, Anastasia G ; Borguet, Eric ; Geiger, Franz M ; Gibbs, Julianne M ; Grassian, Vicki H ; Jun, Young-Shin ; Kabengi, Nadine ; Kubicki, James D ( December 2024 , Nature Communications)

   Solid–water interfaces are crucial for clean water, conventional and renewable energy, and effective nuclear waste management. However, reflecting the complexity of reactive interfaces in continuum-scale models is a challenge, leading to oversimplified representations that often fail to predict real-world behavior. This is because these models use fixed parameters derived by averaging across a wide physicochemical range observed at the molecular scale. Recent studies have revealed the stochastic nature of molecular-level surface sites that define a variety of reaction mechanisms, rates, and products even across a single surface. To bridge the molecular knowledge and predictive continuum-scale models, we propose to represent surface properties with probability distributions rather than with discrete constant values derived by averaging across a heterogeneous surface. This conceptual shift in continuum-scale modeling requires exponentially rising computational power. By incorporating our molecular-scale understanding of solid–water interfaces into continuum-scale models we can pave the way for next generation critical technologies and novel environmental solutions.

    

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5. On scale interactions between the MJO and synoptic scale

   https://doi.org/10.1002/qj.3400  

   Dubey, Sarvesh ; Krishnamurti, Tiruvalam_Natarajan ; Kumar, Vinay ( November 2018 , Quarterly Journal of the Royal Meteorological Society)

   DYNAMO was a field experiment conducted over the near‐equatorial Indian Ocean during 2011 and 2012 for a better understanding of the mechanisms of the Madden–Julian Oscillation (MJO). This study uses DYNAMO observations to study the organization of convection and maintenance of the MJO within the framework of synoptic‐scale weather systems. Lorenz box energetics is used over the limited DYNAMO domain to study the in‐scale energetics (i.e. the exchange of energy within a single scale). Formal scale energetics in the frequency domain is used to study the in‐scale as well as out‐of‐scale interactions (i.e. the exchange of energy among diverse scales) of the kinetic energy (KE) and available potential energy (APE) over limited DYNAMO domain and a zonal belt around the Earth extending 20° north and south of the Equator. The synoptic‐scale precipitation distributions, generation of eddy APE (from the covariance of convective heating and temperature) and its disposition to eddy KE (from the covariance of vertical velocity and temperature) confirm the importance of in‐scale energetics for the maintenance of the synoptic scale. The in‐scale energetics in the frequency domain suggest that conversion of APE to KE on the MJO scale is crucial for its maintenance. Out‐of‐scale energetics suggest that over both domains, MJO loses KE to the synoptic time‐scale (2–7 days), but a reverse situation is encountered in the vicinity of the summer subtropical jet. Overall, MJO is found weakly modulating synoptic scales via transferring eddy KE. These results also imply that out‐of‐scale KE interactions between MJO and synoptic scales are not crucial in understanding the maintenance of the MJO over the DYNAMO domain.

    

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