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Serverless computing, or Function-as-a-Service (FaaS), enables a new way of building and scaling applications by allowing users to deploy fine-grained functions while providing fully-managed resource provisioning and auto-scaling. Custom FaaS container support is gaining traction as it enables better control over OSes, versioning, and tooling for modernizing FaaS applications. However, providing rapid container provisioning introduces non-trivial challenges for FaaS providers, since container provisioning is costly, and real-world FaaS workloads exhibit highly dynamic patterns. In this paper, we design FaaSNet, a highly-scalable middleware system for accelerating FaaS container provisioning. FaaSNet is driven by the workload and infrastructure requirements of the FaaS platform at one of the world's largest cloud providers, Alibaba Cloud Function Compute. FaaSNet enables scalable container provisioning via a lightweight, adaptive function tree (FT) structure. FaaSNet uses an I/O efficient, on-demand fetching mechanism to further reduce provisioning costs at scale. We implement and integrate FaaSNet in Alibaba Cloud Function Compute. Evaluation results show that FaaSNet: (1) finishes provisioning 2,500 function containers on 1,000 virtual machines in 8.3 seconds, (2) scales 13.4× and 16.3× faster than Alibaba Cloud's current FaaS platform and a state-of-the-art P2P container registry (Kraken), respectively, and (3) sustains a bursty workload using 75.2% less time than an optimized baseline. 

Reversible intermolecular interactions play critical roles in nature. However, it is still challenging to monitor the dynamic intermolecular interactions at the single-molecule level in aqueous solution. Here, we studied the dynamic changes of intermolecular interactions at the carboxyl/carboxyl interfaces between a pair of molecules trapped in a plasmonic nanocavity formed between a gold nanoparticle (GNP) and a gold nanoelectrode (GNE). The development of intermolecular interactions, including the appearance of hydrogen bonds (h-bonds), during and after single GNP collision events on the GNE, was monitored by time-resolved surface-enhanced Raman spectroscopy at a tens of milliseconds time resolution. Spectral fingerprints of the carboxyl group corresponding to non-specific intermolecular interactions and h-bonds are identified. Furthermore, we demonstrated that the strength of intermolecular interaction could be mechanically modulated by changing the applied bias at the GNE, which resulted in small and controllable changes in the nanogap distance. Unlike non-specific intermolecular interactions, the intermolecular h-bonds can only be formed stochastically and are more sensitive to the gap distance modulation. This report demonstrates a new approach to modulate and probe intermolecular interactions within nanogaps. 

Creating single‐molecule junctions with a long‐lived lifetime at room temperature is an open challenge. Finding simple and efficient approaches to increase the durability of single‐molecule junction is also of practical value in molecular electronics. Here it is shown that a flexible gold‐coated nanopipette electrode can be utilized in scanning tunneling microscope (STM) break‐junction measurements to efficiently enhance the stability of molecular junctions by comparing with the measurements using conventional solid gold probes. The stabilizing effect of the flexible electrode displays anchor group dependence, which increases with the binding energy between the anchor group and gold. An empirical model is proposed and shows that the flexible electrode could promote stable binding geometries at the gold‐molecule interface and slow down the junction breakage caused by the external perturbations, thereby extending the junction lifetime. Finally, it is demonstrated for the first time that the internal conduit of the flexible STM tip can be utilized for the controlled molecule delivery and molecular junction formation.