Thomas,
The MVStore is obviously your storage of choice going forward - and it has 
nice benefits.  However, in my tests yesterday I inserted ( then updated a 
few times ) a total of 1,696,792 rows.  
This created a dbFile of 8.8GB in size. That works out to 5175.9 bytes per 
row.  The pageStore version was closer to 500 bytes per row.  That is a 
huge difference.
  
But the real kick in the ass was when I shutdown my application - It took 
approx 30 minutes for the db lock file to clean-up so that application 
could be re-started.  That is a show stopper.

I have re-worked my delete to calculate the number of rows I am deleting 
and I will add (n) deletes of 10000 records at a time into a jdbc batch 
statement.  
Hopefully this will prevent the OutOfMemory exception on the delete and I 
am returning to the PageStore.

Thanks for all your work.


On Thursday, July 17, 2014 11:33:19 AM UTC-4, Kenton Garner wrote:
>
> Thanks again Thomas,
>
> I downloaded your latest version and switched back to the MVStore.  I am 
> running tests now.  
> One observation that i have noticed is that with the MVStore enabled the 
> database file is approx 6X the size of when I was using the PageStore.
> I am at approx 1.2 Million messages and the database file is 6+ GB.  When 
> I had 2.1 million records in the PageStore the database file was only about 
> 1GB.
>
> The change log indicated that you have just implemented the start of the 
> auto-compression for the MVStore. Do you expect to see better sizing as 
> this version matures?
> Can you give a quick 10000 foot overview of the overhead differences so 
> that we can determine which version is best for us.  
>
> I have plans to store actual message files in the database.  I tested with 
> the PageStore version and was impressed with the compression I was 
> getting.  
> I am however, concerned with the MVStore version trying to store the same 
> files.  
>
> I can post this question as a new thread if you prefer.
>
>
> On Wednesday, July 16, 2014 3:37:59 AM UTC-4, Thomas Mueller wrote:
>>
>> Hi,
>>
>> > The MSGDATE field is part of the primary key
>>
>> Well, what *exactly* is the primary key? It's not enough if it's _part_ 
>> of the primary key, it needs to be the first column of an index.
>>
>> Out of memory: The problem could be MVCC in combination with the 
>> PageStore, I think this can run out of memory. Could you try using the 
>> MVStore? To do that, you would need to create a new database.
>>
>> Regards,
>> Thomas
>>
>>
>> On Wed, Jul 16, 2014 at 9:28 AM, Noel Grandin <[email protected]> wrote:
>>
>>>
>>>
>>> You shouldn't be getting OOM, even with very large deletes.
>>> Try turning on the heap dump on OOM feature of the JVM, and then running 
>>> the Eclipse Memory Analyzer over the resulting dump.
>>> That should point out the problematic code.
>>>
>>>
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