Hardware accelerators have been a promising solution to reduce the cost of cloud datacenters. This article investigates the acceleration of an important datacenter workload: the web server (or proxy) that faces high computational consumption originated from SSL/TLS processing and HTTP compression. Our study reveals that for the widely-deployed event-driven web architecture, the straight offloading of SSL/TLS or compression tasks suffers from frequent blockings in the offload I/O, leading to the underutilization of both CPU and accelerator resources. To achieve efficient acceleration, we propose QWEB, a comprehensive offload solution based on Intel QuickAssist Technology (QAT). QWEB introduces an asynchronous offload mode for SSL/TLS processing and a pipelining offload mode for HTTP compression, both allowing concurrent offload tasks from a single application process/thread. With these two novel offload modes, the blocking penalty is amortized or even eliminated, and the utilization rate of the parallel computation engines inside the QAT accelerator is greatly increased. The evaluation shows that QWEB provides up to 9x handshake performance with TLS-RSA (2048-bit) over the software baseline. Additionally, the secure data transfer throughput is enhanced by 2x for the SSL/TLS offloading only, 3.5x for the compression offloading only and 5x for the combined offloading.

中文翻译：

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QWEB：具有 QAT 加速的高性能事件驱动 Web 架构

硬件加速器一直是降低云数据中心成本的有前途的解决方案。本文研究了重要数据中心工作负载的加速：面临源自 SSL/TLS 处理和 HTTP 压缩的高计算消耗的 Web 服务器（或代理）。我们的研究表明，对于广泛部署的事件驱动的 Web 架构，直接卸载 SSL/TLS 或压缩任务会在卸载 I/O 中频繁阻塞，导致 CPU 和加速器资源未充分利用。为实现高效加速，我们提出了基于英特尔 QuickAssist 技术 (QAT) 的综合卸载解决方案 QWEB。QWEB 引入了用于 SSL/TLS 处理的异步卸载模式和用于 HTTP 压缩的流水线卸载模式，两者都允许从单个应用程序进程/线程并发卸载任务。通过这两种新颖的卸载模式，分摊甚至消除了阻塞惩罚，大大提高了 QAT 加速器内部并行计算引擎的利用率。评估表明，QWEB 使用 TLS-RSA（2048 位）在软件基线上提供高达 9 倍的握手性能。此外，仅 SSL/TLS 卸载的安全数据传输吞吐量提高了 2 倍，仅压缩卸载提高了 3.5 倍，组合卸载提高了 5 倍。评估表明，QWEB 使用 TLS-RSA（2048 位）在软件基线上提供高达 9 倍的握手性能。此外，仅 SSL/TLS 卸载的安全数据传输吞吐量提高了 2 倍，仅压缩卸载提高了 3.5 倍，组合卸载提高了 5 倍。评估表明，QWEB 使用 TLS-RSA（2048 位）在软件基线上提供高达 9 倍的握手性能。此外，仅 SSL/TLS 卸载的安全数据传输吞吐量提高了 2 倍，仅压缩卸载提高了 3.5 倍，组合卸载提高了 5 倍。