DOC PREVIEW
MIT 6 830 - Optimizing Distributed Read-Only Transactions Using Multiversion Concurrency

This preview shows page 1-2-3-4 out of 12 pages.

Save
View full document
View full document
Premium Document
Do you want full access? Go Premium and unlock all 12 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 12 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 12 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 12 pages.
Access to all documents
Download any document
Ad free experience
Premium Document
Do you want full access? Go Premium and unlock all 12 pages.
Access to all documents
Download any document
Ad free experience

Unformatted text preview:

Optimizing Distributed Read-Only TransactionsUsing Multiversion ConcurrencyDan Ports Austin Clements Irene ZhangTuesday, December 11, 2007Dan Ports, Austin Clements, Irene Zhang Optimizing Distributed Read-Only TransactionsDistributed TransactionsDistributed transactions are usefulfor many applications...but slowDan Ports, Austin Clements, Irene Zhang Optimizing Distributed Read-Only TransactionsDistributed TransactionsDistributed transactions are usefulfor many applications...but slowDan Ports, Austin Clements, Irene Zhang Optimizing Distributed Read-Only TransactionsSystem ArchitectureBlock serverClient libraryCache CacheClient libraryApplication Application· · ·Dan Ports, Austin Clements, Irene Zhang Optimizing Distributed Read-Only TransactionsSystem ArchitectureBlock serverClient libraryCache CacheClient libraryNode NodeDB frontend DB frontendDB client DB client DB client DB clientDan Ports, Austin Clements, Irene Zhang Optimizing Distributed Read-Only TransactionsSystem ArchitectureBlock serverClient libraryCache CacheClient libraryNode NodeFS frontend FS frontendApplication Application Application ApplicationDan Ports, Austin Clements, Irene Zhang Optimizing Distributed Read-Only TransactionsDistributed Transactions Can Be FastLower isolation levels?e.g. READ COMMITTED, snapshot isolation, ...any hope for correctness? sanity?Our solution:weaken causality instead of serializabilityAll operations transactionally consistentRead only transactions may run slightly in pastDan Ports, Austin Clements, Irene Zhang Optimizing Distributed Read-Only TransactionsDistributed Transactions Can Be FastLower isolation levels?e.g. READ COMMITTED, snapshot isolation, ...any hope for correctness? sanity?Our solution:weaken causality instead of serializabilityAll operations transactionally consistentRead only transactions may run slightly in pastDan Ports, Austin Clements, Irene Zhang Optimizing Distributed Read-Only TransactionsProperties1Serializability2-Freshness3r/o transactions do not block or abort4Local CausalityAnomaly: acausalityA read-only transaction may not see the results of atransaction that just committed on another node.Dan Ports, Austin Clements, Irene Zhang Optimizing Distributed Read-Only TransactionsProperties1Serializability2-Freshness3r/o transactions do not block or abort4Local CausalityAnomaly: acausalityA read-only transaction may not see the results of atransaction that just committed on another node.Dan Ports, Austin Clements, Irene Zhang Optimizing Distributed Read-Only TransactionsPerformanceBuilt ext2-like filesystem atop block storeReplayed 20,000 operations over 13 minutesfrom Berkeley NFS server trace116 parallel clientsInferred transactions (open-close)2 second allowable stalenessCompared against standard OCCDan Ports, Austin Clements, Irene Zhang Optimizing Distributed Read-Only TransactionsPerformancePlain OCC Read-Opt. ImprovementNetwork 15.0 MB 11.0 MB 27%Aborts 392 22 94%CPU time 14.5 min. 35 sec. 96%Dan Ports, Austin Clements, Irene Zhang Optimizing Distributed Read-Only


View Full Document

MIT 6 830 - Optimizing Distributed Read-Only Transactions Using Multiversion Concurrency

Download Optimizing Distributed Read-Only Transactions Using Multiversion Concurrency
Our administrator received your request to download this document. We will send you the file to your email shortly.
Loading Unlocking...
Login

Join to view Optimizing Distributed Read-Only Transactions Using Multiversion Concurrency and access 3M+ class-specific study document.

or
We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view Optimizing Distributed Read-Only Transactions Using Multiversion Concurrency 2 2 and access 3M+ class-specific study document.

or

By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?