lucene-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Steven Rowe (JIRA)" <>
Subject [jira] Created: (LUCENE-1719) Add javadoc notes about ICUCollationKeyFilter's speed advantage over CollationKeyFilter
Date Sun, 28 Jun 2009 04:48:47 GMT
Add javadoc notes about ICUCollationKeyFilter's speed advantage over CollationKeyFilter

                 Key: LUCENE-1719
             Project: Lucene - Java
          Issue Type: Improvement
          Components: contrib/*
    Affects Versions: 2.4.1
            Reporter: Steven Rowe
            Priority: Trivial
             Fix For: 2.9

contrib/collation's ICUCollationKeyFilter, which uses ICU4J collation, is faster than CollationKeyFilter,
the JVM-provided java.text.Collator implementation in the same package.  The javadocs of these
classes should be modified to add a note to this effect.

My curiosity was piqued by [Robert Muir's comment|]
on LUCENE-1581, in which he states that ICUCollationKeyFilter is up to 30x faster than CollationKeyFilter.

I timed the operation of these two classes, with Sun JVM versions 1.4.2/32-bit, 1.5.0/32-
and 64-bit, and 1.6.0/64-bit, using 90k word lists of 4 languages (taken from the corresponding
Debian wordlist packages and truncated to the first 90k words after a fixed random shuffling),
using Collators at the default strength, on a Windows Vista 64-bit machine.  I used an analysis
pipeline consisting of WhitespaceTokenizer chained to the collation key filter, so to isolate
the time taken by the collation key filters, I also timed WhitespaceTokenizer operating alone
for each combination, and then subtracted it from both of the collation key analysis chains'
times.  The rightmost column represents the performance advantage of the ICU4J implemtation
(ICU) over the java.text.Collator implementation (JVM), after discounting the WhitespaceTokenizer
time (WST): (ICU-WST) / (JVM-WST). The best times out of 5 runs for each combination, in milliseconds,
are as follows:

||Sun JVM||Language||java.text||ICU4J||WhitespaceTokenizer||ICU4J Improvement||
|1.4.2_17 (32 bit)|English|522|212|13|2.6x|
|1.4.2_17 (32 bit)|French|716|243|14|3.1x|
|1.4.2_17 (32 bit)|German|669|264|16|2.6x|
|1.4.2_17 (32 bit)|Ukranian|931|474|25|2.0x|
|1.5.0_15 (32 bit)|English|604|176|16|3.7x|
|1.5.0_15 (32 bit)|French|817|209|17|4.2x|
|1.5.0_15 (32 bit)|German|799|225|20|3.8x|
|1.5.0_15 (32 bit)|Ukranian|1029|436|26|2.4x|
|1.5.0_15 (64 bit)|English|431|89|10|5.3x|
|1.5.0_15 (64 bit)|French|562|112|11|5.5x|
|1.5.0_15 (64 bit)|German|567|116|13|5.4x|
|1.5.0_15 (64 bit)|Ukranian|734|281|21|2.7x|
|1.6.0_13 (64 bit)|English|162|81|9|2.1x|
|1.6.0_13 (64 bit)|French|192|92|10|2.2x|
|1.6.0_13 (64 bit)|German|204|99|14|2.2x|
|1.6.0_13 (64 bit)|Ukranian|273|202|21|1.4x|

This message is automatically generated by JIRA.
You can reply to this email to add a comment to the issue online.

To unsubscribe, e-mail:
For additional commands, e-mail:

View raw message