WheelFS

Jeremy Stribling, Frans Kaashoek, Jinyang Li, Robert Morris

MIT CSAIL and New York University

I Want to Publish an SOSP Paper

• But I don’t want to do a lot of work

• Idea: New cooperative Web cache!

Exploit a Network File System

Network File Server(/mnt/awesome-cdn/cache)

ApacheCachingProxy

ApacheCachingProxy

ApacheCachingProxy

ApacheCachingProxy

foo.html

It Is Too Good to Be True

• Tries to mask failures with long timeouts

• Strict consistency prevents use of cached data under failures

• My naïve SOSP strategy might not work

So What Are My Options?

• Give up dream and just not graduate• Submit random paper [Rooter, WMSCI ’05]

• Build an FS that would work for real apps– Apache can use old copies of data– And can always fall back to the origin– Why not tell the FS?

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(Joules)

-1.575

-1.57

-1.565

-1.56

-1.555

-1.55

-1.545

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(Percent)

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(dB)

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(# CPUs)

-1.575

-1.57

-1.565

-1.56

-1.555

-1.55

-1.545

0 0.5 1 1.5 2 2.5 3

(# nodes)

WheelFS: Storage for Wide-area Apps

• File system API

• Semantic cues give apps control of behavior under failures

Make Apache distributed with 1 line change

WheelFS WheelFS WheelFS WheelFS

Cooperative Web Cache on WheelFS

ApacheCachingProxy

ApacheCachingProxy

ApacheCachingProxy

ApacheCachingProxy

/wfs/cache/ /.bestversion.maxtime=500 /.lax /$URL

Use newest version you can find quicklyTime out operations after T millisecondsAllow multiple versions of a directory to be updated

I’m Running Out of Time, So:

• A compact but powerful set of cues

• Useful to other applications, including:– PlanetLab measurement studies– Parallel Grid computations– Distribute make

• See you at the next big conference!