Mailing-List: contact derby-dev-help@db.apache.org; run by ezmlm
Precedence: bulk
Reply-To: "Derby Development" <derby-dev@db.apache.org>
Message-ID: <771428706.1103573954099.JavaMail.apache@nagoya>
Date: Mon, 20 Dec 2004 12:19:14 -0800 (PST)
From: "Sunitha Kambhampati (JIRA)" <derby-dev@db.apache.org>
To: derby-dev@db.apache.org
Subject: [jira] Created: (DERBY-108) Document performance tip for inserts in
 tuning guide
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit

Document performance tip for inserts in tuning guide
----------------------------------------------------

         Key: DERBY-108
         URL: http://nagoya.apache.org/jira/browse/DERBY-108
     Project: Derby
        Type: Improvement
  Components: Documentation  
    Versions: 10.0.2.1    
    Reporter: Sunitha Kambhampati
    Priority: Minor
     Fix For: 10.0.2.2


Need to add this important performance tip in the tuning guide document.
Could probably be added as Tip #8 in http://incubator.apache.org/derby/manuals/tuning/perf20.html#HDRSII-PERF-25864
----------------------------------------------
Avoid inserts in autocommit mode if possible:
Inserts can be painfully slow in autocommit mode. The reason is that each commit involves a flush of the log to the disk  for each insert statement. The commit will not return until a physical disk write has been executed. 

To speed things up, there are 2 possibilities
- Run in autocommit false mode and execute a number of inserts in one transaction and then explicitly issue a commit. 
- If your application allows an initial load into the table, one can use the import system procedures to insert data into a table. 
http://incubator.apache.org/derby/manuals/tools/tools90.html#HDRSII-IMPORT-57005.
If loading into an empty table using these interfaces, derby will not log the
individual inserts. The reason is  recovery understands that a backout of this
operation is an empty table, and the data in the table is forced to
disk before the transaction commits.


--------------------------------------------
References from derby mailing lists:
http://nagoya.apache.org/eyebrowse/ReadMsg?listName=derby-user@db.apache.org&msgNo=363
http://nagoya.apache.org/eyebrowse/ReadMsg?listId=271&msgNo=335


-- 
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators:
   http://nagoya.apache.org/jira/secure/Administrators.jspa
-
If you want more information on JIRA, or have a bug to report see:
   http://www.atlassian.com/software/jira