Title: Snowbird: Interactive Resource-Intensive Applications Made Easy
1SnowbirdInteractive Resource-IntensiveApplicati
ons Made Easy
- H. Andrés Lagar-Cavilla
- Niraj Tolia , Eyal de Lara,
- M. Satyanarayanan Dave OHallaron
- University of Toronto, HP Labs,
- Carnegie Mellon University
- Middleware, November 2007
2Bimodal Applications
- Interactive
- Cognitive phase
- Resource-Intensive
- Crunch phase
- Digital Animation
- Scientific Computing
- Engineering Design
- Bio/Pharma
- Video Editing
- .
Maya (digital animation)
3Dichotomy
- Crunch (computation)
- Short completion time
- Remote computing resources
- Cognitive (interaction)
- Crisp interactive performance
- User attention
4Execution Alternatives
- Thick Clients (Desktop PCs)
- Cognitive excellent interactive performance
- Crunch resource constrained
- Thin Clients (VNC, Remote Desktop)
- Crunch use of remote resources (CPU, Data)
- Cognitive latency and jitter impact
interactions - Custom Applications
- Pipeline placement over different nodes
- Requires significant developer resources
5Execution Alternatives
-
- Cognitive excellent interactive performance
-
-
- Crunch use of remote resources (CPU, Data)
-
-
-
-
6Snowbird Agent Abstraction
- Applications encapsulated within an agent
- Agent processes, libraries, IPC, OS, config
data - Migration performance goals achieved by morphing
- a thin client for resource intensive crunch
phases - a thick client for highly interactive cognitive
phases
7Bimodal Applications Made Easy
- Develop apps as monolithic blocks
- Dont worry about what executes where
- Agent is migrated to satisfy each phase
- Seamless and transparent behavior
- Legacy support
- Different OSs (and versions/features)
- Different languages (Fortran!)
- No need for recompilation, relinking, etc
- Closed source apps just work
8Implementation
9Design Criteria
- VM-based migration
- x86 interface most widely deployed
- Transparently support OS, lang, etc
- Internet scale
- WAN migration
- Long fat pipes 50 Mbp/s, 50-200 ms RTT
- Use of graphics HW acceleration a must
- For the cognitive mode of bimodal apps
- Server-less design (P2P)
- All hosts symmetric
- Can execute anywhere
10Components
- VMM suspend, resume, live migration
- Xen 3.0.1
- Interaction-aware migration manager
- Transparent
- Support for 3D acceleration in VMs
- Vital for crisp interaction
- Virtual disk that maximizes locality
- WAN area migration
11Agent Profiles Migration Manager
- FSM that models an agents behavior
- Provided by expert users, admins, or developers
- Default system-wide profile available
- Only deployment additional effort
12Interaction-aware
- Novelty in our approach
- Measure the quality of the interactive response
- We use frames per seconds
- More in sync with operations in bimodal apps
- Stretch object, rotate, zoom, etc
- Pure latency not enough
- Ample space for future work
13Frames Per Second
- Non work-conserving (VNC) FPS 2/latency
- Work-conserving (X) FPS n/(latencyk)
14The Rest
- VMGL support for 3D acceleration in VMs
- Coming live to this conference in 5 mins
- Follow up VEE 2007, gt4K downloads
- WANDisk virtual disk maximizes locality
- Minimizes WAN communication
- Simplifies state synchronization
- More details in paper
15Evaluation
16Benchmarks
- Broad set of domains
- Scientific Computing, Bio, Video Editing,
Animation - Closed and open source
- Straightforward installation
- Able to use generic profile on all four
- Partitioned mode for comparison
- ADF Maya
QuakeViz
Kmenc15
Maya (closed source)
ADF (closed source)
17Methodology
- Crunch cognitive benchmarks
- Performing crunch experiments is easy
- Replaying long interactive traces is not
- Cant expect a user to do it
- Must be able to compare results
- VNC-Redux record and replay interactive user
sessions - Record input and screen state
- This is matched during replay for accuracy
18Experimental Setup
19Results Crunch Phase
370Ouch!
- Snowbirds crunch performance
- Much better than thick
- Comparable to thin/partitioned
20Results Cognitive Phase
- Better interactivity than thin clients
- Is Snowbird any worse than a thick client?
- gt 20 FPS is ok, lt 8 FPS is unusable
21Take Home Messages
- Bimodal applications
- What they are and why they matter
- Thin clients are not almighty
- There is no replacement for local interaction
- Best of both worlds thick and thin clients
- Necessary in an Internet world with remote
computing resources - VM-based app migration is feasible
- And with many advantages
- Future trends align well
22Futurism
- More bandwidth cheaper VM migration
- What about latency?
- The earth is not shrinking
- Speed of light is not increasing
- More routers, overlays, firewalls
- Toronto-London UK 109ms
- Toronto-LA 84ms
- Insurmountable obstacle for thin clients
23Questions?
Thanks ?
H. Andrés Lagar-Cavilla andreslc_at_cs.toronto.edu N
iraj Tolia, Eyal de Lara, Satya Dave
OHallaron U of Toronto, HP Labs, Carnegie Mellon
24Backup
25VMGL 3D Acceleration in VMs
- OpenGL virtualization
- Hardware specs closed, unavailable
- Focus instead on software standards
- OpenGL -gt cross-platform
- Direct3D -gt MS-only
- Intercept GL calls and forward them to the host.
Proprietary driver renders there. - More details VEE 2007
26Open GL for X11 Apps
27VMGL for X11 Apps
28WANDisk Virtual Disk
Chunk Table
foo.toronto.edu
ChunkMisses
29Why Another Storage System?
- Exploits Snowbird characteristics
- P2P model
- No server interposition
- Single-writer simple metadata, no locks
- Minimizes WAN talk
- Locality persistent replicas
- Differential transfers rsync
- On-demand fetching
30Experimental Setup
- Thick No virtualization, on User Desktop
- User Desktop UP with graphics acceleration
- Thin No virtualization, on Compute Server
- Compute Server 4-way SMP
- 100 Mbit/s WAN, RTT 33, 66, and 100 ms
- Partitioned
- App-specific developer-brewed Maya ADF
- Snowbird
- Agents are initially launched on User Desktop
31ADF Migration Time (secs)
Latency (ms) Detection Migration Pause
33 12.5 62 4.9
66 11.5 62 6.2
100 13.1 64.9 6.7
32Applicability of Snowbird
- Morphing time our implementation
- Speedup application resources
- C Crunch phase time locally
33Snowbird Limitations
- Parallelism up to SMP level
- What about cluster-scale?
- SSE, 3DNow!
- i.e. x86 is not that uniform
- Overlapping phases
- Hysteresis, priority in migration manager
- Very short phases
- Cost/benefit analysis
34Our Current Interests
- VM support for large parallel tasks
- Relevant to commodity computing
- Migration, the cloud, etc
- How to measure interactive performance
- Thin clients, desktop consolidation, VMs
- Unknown effects for modern (3D-heavy) GUIs
35Really Backup Backup
36Keywords Of This Presentation
- Thin clients
- Remote execution
- Interactive Performance
- Thick clients
- Virtual machine migration
- Application migration
- Bimodal applications
- What they are and why they matter
37Frames Per Second
- Non work-conserving same latency, less frames
- Work-conserving same frames, more latency
38What We Need
- System support for bimodal applications
- Combine best of both worlds
- Thick client, local execution
- Interaction
- Thin client, remote execution
- Computation
- Make development easy
39Results Crunch Phase
- Snowbirds crunch performance
- Much better than thick
- Comparable to thin/partitioned
40Talk Pointers
- Be more explicit demo thin, frames
- Proxy FPS input in migr manager