[
https://issues.apache.org/jira/browse/DERBY-1664?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Rick Hillegas updated DERBY-1664:
---------------------------------
Attachment: derby_1664.java
Attaching derby_1664.java. This program uses System.currentTimeMillis() to
measure how long the following operations take:
DRIVERLOAD -- The time to execute Class.forName(
"org.apache.derby.jdbc.EmbeddedDriver" )
DBCREATE -- The time to execute DriverManager.getConnection( dbName +
";create=true" );
DBCLOSE -- The time to execute DriverManager.getConnection( dbName +
";shutdown=true" );
REOPEN -- The time to execute DriverManager.getConnection( dbName );
TABLECREATE -- The time to execute Connection.prepareStatement( "create table
t( a int )" ).execute()
Each run of the program creates a configurable number of databases, performing
the above operations. The first database takes the longest, presumably because
it involves faulting in a lot of Derby classes. The program can be run against
on-disk and in-memory databases. I ran the program 10 times for on-disk and 10
times for in-memory databases. For each run, I created 10 databases. I then ran
the accumulated log script to generate the following results. I ran this test
on my macbook pro laptop (10.7 trunk on Java 7 on Mac OSX 10.5.8).
This is the script I used to drive the program:
rm derby_1664.sql
for counter in 0 1 2 3 4 5 6 7 8 9
do
echo Run number $counter...
java derby_1664 $counter memory 10
java derby_1664 $counter disk 10
done
These are the performance numbers for the first database, the one which incurs
the brunt of the classloading. The numbers are averaged over the 10 runs of the
program. The first column describes the configuration, which is either DISK
(on-disk databases) or MEMORY (in-memory databases):
CONFIGURA&|DRIVERLOAD |DBCREATE |DBCLOSE
|REOPEN |TABLECREATE
-------------------------------------------------------------------------------------------------------------------
DISK |450 |1123 |36 |33
|174
MEMORY |496 |950 |11 |20
|167
These are the performance numbers averaged over the subsequent databases, again
averaged over the 10 runs of the program:
CONFIGURA&|DRIVERLOAD |DBCREATE |DBCLOSE
|REOPEN |TABLECREATE
-------------------------------------------------------------------------------------------------------------------
DISK |0 |486 |13 |22
|15
MEMORY |0 |267 |5 |14
|7
I am puzzled that DRIVERLOAD consistently takes longer for in-memory databases
than for on-disk databases.
> Derby startup time is too slow
> ------------------------------
>
> Key: DERBY-1664
> URL: https://issues.apache.org/jira/browse/DERBY-1664
> Project: Derby
> Issue Type: Improvement
> Components: Store
> Reporter: David Van Couvering
> Attachments: derby_1664.java, perftest.diff
>
>
> I know it's hard to measure what "too slow" is, but this is a common
> complaint and this affects overall perception of Derby. This appears to be
> related to another common complaint that it takes too long to create tables.
> I am marking this as Urgent because of the impact it has to Derby perception
> and the fact that the 10.2 release is going to get such wide distribution
> through the Sun JDK.
> For background, see http://www.nabble.com/Startup-time-tf2012748.html#a5531684
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
