Configuration and Performance Trade-off for Striping

Lustre file system striping options for optimal performance.

For maximum aggregate performance, it is important to keep all OSTs occupied. The following circumstances should be considered when striping a Lustre file system.

Single OST

When many clients in a parallel application are each creating their own files, and where the number of clients is significantly larger than the number of OSTs, the best aggregate performance is achieved when each object is put on only a single OST.

Multiple OSTs

At the other extreme, for applications where multiple processes are all writing to one large (sparse) file, it is better to stripe that single file over all of the available OSTs. Similarly, if a few processes write large files in large chunks, it is a good idea to stripe over enough OSTs to keep the OSTs busy on both the write and the read path.