The 2015 papers themselves reside permanently in the ACM Digital Library. Before the papers arrive in the Digital Library (about October 4th), the links provided here go to preview versions of the papers, stored locally; after the papers appear in the Digital Library, those links will be replaced by links providing free access to the copies in the Digital Library.
Before and during the conference, this web site also contains single-column versions of the papers, designed for reading on smaller devices. These will be deleted after the conference.
This web site includes the SOSP archive, with tables-of-contents for all the previous SOSP conferences, and links to the papers’ citation pages in the Digital Library (if available), or to the papers stored on this web site.