1 / 18

Efficient Application Placement in a Dynamic Hosting Platform

Efficient Application Placement in a Dynamic Hosting Platform. Zakaria Al-Qudah – CWRU Hussein Alzoubi – CWRU Mark Allman – ICSI Michael Rabinovich – CWRU Vincenzo Liberatore - CWRU. Target Environment: Dynamic Hosting. General components App servers Local controllers Central controller

lluvia
Télécharger la présentation

Efficient Application Placement in a Dynamic Hosting Platform

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Efficient Application Placement in a Dynamic Hosting Platform Zakaria Al-Qudah – CWRU Hussein Alzoubi – CWRU Mark Allman – ICSI Michael Rabinovich – CWRU Vincenzo Liberatore - CWRU

  2. Target Environment: Dynamic Hosting • General components • App servers • Local controllers • Central controller • Request router • Measurement modules

  3. Our Problem: Enactment of resource allocation decisions • Starting applications is slow and resource-intensive • Causes loss in system responsiveness • Limits flexibility of resource allocation

  4. Option 1: “Run Everywhere” • Run an instance of every application on every machine • Send requests only to those intended to be active • Intuition: idle application instances should not consume resources

  5. Run-Everywhere Results • Conclusion: Run-everywhere is impractical

  6. Option 2: Explicit Suspend/Resume • What was the problem of run-everywhere? • OS couldn’t tell active applications from idle ones due to the periodic application maintenance • Solution: explicitly convey this information to the OS • Suspend idle applications with SIGSTOP • Resume to activate with SIGCONT

  7. Still inefficiencies: Much better! • On-demand page-in OS brings a page to memory only when it’s referenced  context switching • On-demand page-out Full memory at the time of page-in  resumption waits for page-out • On-demand eviction of memory pages to disk Piecemeal eviction  process state spreads over many disjoined locations on disk

  8. Enhanced Suspend/Resume • Bring all the process pages at once from disk to memory (prefetching) • Whenever an application is suspended, evict it out of memory at once (pre-purging) • This keeps process state in few contiguous places on disk Prefetching/prepurging = ancient swapping! …but only for application placement

  9. Performance Evaluation: Startup time

  10. Performance Evaluation: Resource consumption

  11. Prefetching overhead

  12. Performance Evaluation: Contributing factors

  13. End-to-end responsiveness: Experiment setup

  14. End-to-end responsiveness - results

  15. End-to-end responsiveness (cont’d)

  16. Limitations of Suspend-Resume • Consequences of bad programming practices are more pronounced • Less useful for clustered applications • Re-joining the cluster takes long time (regardless of how applications are started)

  17. Future work: Virtualization • Various technologies • OS-level (e.g., OpenVZ) • Hardware-level (e.g., VMware) • Vary in performance overhead and offered features (arguably!) • Degree of performance/fault/security isolation • Ability to run heterogeneous OSes on the same hardware • Similar suspend-resume issues might apply • Bulk prepurging • Bulk prefetching

  18. Summary • Most existing work on dynamic hosting focuses on resource allocation decisions • We focus on efficient enactment of these decisions • Examined several alternatives for application placement • Deployment from scratch • Run-everywhere • Suspend-resume • Enhanced suspend-resume • Swapping for application placement • Normal paging for active tasks • Enhanced suspend-resume is significantly more efficient

More Related