Hi,

Some initial results: you can shrink the database by running "shutdown
compact" or "shutdown defrag". Each time this is run, it shrinks a few MB
(up to some point, of course). This works, but it's relatively slow. Now
the task is to make it faster. There are two ways: shrink it fully to the
minimum size, and shrink it incrementally (like now) but faster. I'm
working on that now.

Regards,
Thomas



On Tue, May 6, 2014 at 11:39 AM, Steve McLeod <[email protected]>wrote:

> Hi Thomas,
>
> I've sent you a private email with a link to the new database file, made
> with H2 1.4.178
>
> Regards,
>
> Steve
>
>
> On Monday, 5 May 2014 07:46:16 UTC+2, Thomas Mueller wrote:
>
>> Hi,
>>
>> The database file should shrink if you run "shutdown defrag".
>>
>> The current compact algorithm is quite inefficient, that means the
>> databases file is quite big on average. The highest priority is still to
>> ensure it always works correctly, and when that's done I will work on more
>> efficiently re-using disk space and specially compact the file faster when
>> closing the database.
>>
>> Could you send me the new database file? It would be nice to have a
>> real-world database file to test this. The last file you sent helped a lot,
>> thanks to it I found some problems that completely prevented the file to
>> shrink.
>>
>> Regards,
>> Thomas
>>
>>
>>
>> On Sunday, May 4, 2014, Steve McLeod <[email protected]> wrote:
>>
>>> Hi Thomas,
>>>
>>> I tested the same large data import with H2 1.4.178, and there is no
>>> improvement over H2 1.4.177.
>>>
>>> Here are the file sizes, in both cases after the app has stopped:
>>>
>>> H2 1.3.176: pokercopilot.h2.db  301,669,352  bytes
>>> H2 1.4.178: pokercopilot.mv.db 1,023,037,440  bytes
>>>
>>> Let me know what I can do to help.
>>>
>>> Regards,
>>>
>>> Steve
>>>
>>>
>>> On Saturday, 19 April 2014 11:44:05 UTC+2, Steve McLeod wrote:
>>>
>>> Hi Thomas,
>>>
>>> Great! Glad I could help make your superb product even better.
>>>
>>>
>>>
>>> On Friday, 18 April 2014 21:38:27 UTC+2, Thomas Mueller wrote:
>>>
>>> Hi,
>>>
>>> Thanks a lot for the database! I know what the problem is now, but I
>>> couldn't fix it yet. The database file (pokercopilot2.mv.db) has about 181
>>> MB of "live" data, the rest (about 78%) is not used. The mechanism to get
>>> rid of the unused space is not working as it should for this case (I think
>>> the problem is that b-tree nodes are not processed correctly). This will be
>>> fixed in the next release.
>>>
>>> Regards,
>>> Thomas
>>>
>>>
>>> On Fri, Apr 18, 2014 at 5:29 PM, Steve McLeod <[email protected]>wrote:
>>>
>>> Hi Thomas,
>>>
>>> I've sent a link to file privately to your email address.
>>>
>>> Regards,
>>>
>>> Steve
>>>
>>>
>>>
>>> On Friday, 18 April 2014 14:04:37 UTC+2, Thomas Mueller wrote:
>>>
>>> Hi,
>>>
>>> Hm, that didn't help much. Could you send me the (compressed) database
>>> files please? If it's too big, what is the compressed size of the files?
>>>
>>> Regards,
>>> Thomas
>>>
>>>
>>> On Fri, Apr 18, 2014 at 1:07 PM, Steve McLeod <[email protected]>wrote:
>>>
>>> Hi Thomas,
>>>
>>> Thanks for the suggestion. I tried adding ";retention_time=1000" to the
>>> URL, and this resulted in a small improvement.
>>>
>>> pokercopilot.h2.db  302,018,560  bytes
>>> pokercopilot.mv.db 999,120,896  bytes
>>> pokercopilot.mv.db with RETENTION_TIME=1000:  811,728,896 bytes
>>>
>>> These numbers all reflect a loading of data in a newly created database
>>> that consisted of roughly 2,400,000 INSERTS and UPDATES with plenty of
>>> SELECTS and almost no DELETES. After the loading was complete, I let the
>>> application keep running with the database open for a few minutes, then
>>> close the application and therefore the database.
>>>
>>> Here is the full JDBC url I'm using:
>>> jdbc:h2:/Users/steve/Library/Application Support/com.barbarysoftware.po
>>> kercopilot/database/pokercopilot;DATABASE_EVENT_LISTENER='co
>>> m.barbarysoftware.pokercopilot.database.DatabaseListener';COMPRESS_
>>> LOB=DEFLATE;CACHE_SIZE=65536;RETENTION_TIME=1000
>>>
>>> Let me know if there is anything else I can do to help diagnose this.
>>>
>>> Regards,
>>>
>>> Steve
>>>
>>>
>>>
>>>
>>> On Thursday, 17 April 2014 17:15:50 UTC+2, Thomas Muel
>>>
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