db-derby-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Suresh Thalamati <suresh.thalam...@gmail.com>
Subject Re: [PATCH] Derby 218 - Add relaxed durability option
Date Mon, 02 May 2005 18:05:40 GMT
sure.  I will  review it.

Mike Matrigali wrote:

> suresh, you have done a lot of work in this area could you review
> the patch and post your comments?
> Sunitha Kambhampati wrote:
>> A little background: Sometime earlier on the list, Dan posted a fix 
>> to make derby go faster with relaxed durability with some flags.  The 
>> post is at 
>> http://article.gmane.org/gmane.comp.apache.db.derby.user/681/match=relaxed+durability

>> This mode is very useful for unit testing or at development time when 
>> recoverability is not required.
>> Basically in this mode, syncs are disabled for logs, data writes at 
>> checkpoint, page allocation when file is grown; - what this means is 
>> that data is not flushed all the way to the disk and in most cases 
>> i/o cost is not involved. Note,  code already exists in Derby to do 
>> this.
>> So for Derby 218, This  patch addresses the following requirements:  
>> 1) Have a single property to enable this relaxed durability mode, so 
>> it is easy for users  to enable it.
>> 2) Print message to derby.log that this mode is enabled
>> 3) A way to report boot errors that may be because of this option 
>> being enabled. What this maps to is - have a marker to recognize that 
>> database was booted in this mode, and then on subsequent boot; if 
>> errors happen during recovery - report a message that it could have 
>> happened because of this mode being set.
> > ... deleted ...

View raw message