Research of performance of cloud synchronization services like ownCloud, Seafile and Dropbox has shown, that on-premise services show better performance characteristics than public clouds syncing big files (higher transfer rates in both upload and download could be obtained due to simple implementation and smaller activity of users for specific bandwidth) and are very competitive syncing mixtures of files.
Unlike typical web services, cloud sync and share is characterized by requests load/number much outreaching the typical loads to the web server per user in some specific activity cases. Underutilized upload/download bandwidth and long distribution tails (penalizing transfers of small files over WAN) are characteristic for services using current ownCloud synchronization protocol. Important factor in synchronization performance is also number of operations performed per single-file request on the web-server. In some specific mime-type cases, the complete file has to be uploaded or downloaded because of a small change in the file body, consuming server resources.
In the contribution, the tests of sync optimizations prototypes – requests bundling, http/2, delta-sync and requests scheduling - addressing the above issues, will be presented.