<< Back to previous view

[CLJ-668] Improve slurp performance by using native Java StringWriter and jio/copy Created: 01/Nov/10  Updated: 21/Apr/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.3
Fix Version/s: None

Type: Enhancement Priority: Major
Reporter: Jürgen Hötzel Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: io, newbie, performance

Approval: Triaged

 Description   

Instead of copying each character from InputReader to StringBuffer.

Performance improvement:

From:
user> (time (count (slurp "/home/juergen/test.dat")))
"Elapsed time: 4269.980863 msecs"
104857600
To:
user> (time (count (slurp "/home/juergen/test.dat")))
"Elapsed time: 1140.854023 msecs"
104857600

Patch: http://github.com/juergenhoetzel/clojure/commit/af1a5713cd485ba5f1db25c37906ebaf7d474b47



 Comments   
Comment by Alex Miller [ 21/Apr/14 3:28 PM ]

This is double-better with the changes in Clojure 1.6 to improve jio/copy performance by using the NIO impl. Rough timing difference on a 25M file: old= 2316.021 msecs, new= 93.319 msecs.

Filer did not supply a patch and is not a contributor. If someone wants to make a patch (and better timing info demonstrating performance improvements), that would be great.

Generated at Fri Aug 29 15:10:15 CDT 2014 using JIRA 4.4#649-r158309.