Performance Analysis of Aerie under Mail Server Workloads

Inspite of the rapid advancements in storage technology, the fundamental architecture of storage in operating system remains fixed. Applications invoke the kernel to store and retrieve data and kernel invokes the file system. Recent work suggests a new class of memory called storage class memory(SCM) which blurs out the distinction between fast, expensive and volatile memory, and slow, cheap and non-volatile storage. The file system for such a class of memory does not need kernel interaction. Applications can modify the file system and optimize it according to their needs. One such flexible file system architecture is provided by Aerie [13]. It exposes storage class memory to user mode programs which allows direct access to memory from user mode. Aerie[13] evaluates the application level performance on three Filebench profiles: file server, web server and web proxy. We are interested in measuring the performance of Aerie for mail server profiles. Mail servers usually deal with a large number of small files which are in constant flux. It has frequent reads/writes, create/delete and appends. In this paper, we adopt two simple benchmarks which mimic the behavior of a mail server and alter them to use the file system APIs exposed by Aerie. We compare the performance of Aerie with tmpfs and ext3 file system (with and without caching) on linux 3.2.2.