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From Sundar Narayanaswamy <sundar...@yahoo.com>
Subject Re: SYSCS_UTIL.SYSCS_INPLACE_COMPRESS_TABLE question
Date Tue, 01 Nov 2011 10:29:09 GMT

Mike, Thanks for looking into the issue. I think it would work if inplace
compress got table level locks during purge. Would the improvement you are
considering help when Derby tries to reclaim space outside of the inplace
compress procedure as well ? That would be great ! I have read from the
Derby docs that Derby tries to reuse space from deleted rows for future
inserts (even without inplace compress), but, I found that wasn't happening
in my case. I was hence trying to use inplace compress with purge_rows
option. 

Please let me know if/how I can help further.


Mike Matrigali wrote:
> 
> I am thinking about this issue, thank you for reporting.
> 
> Your application is the 2nd worst case for Derby.  I don't know if we 
> can fix at row level, but there may be some extra work we can do to try
> and get table level locks and do page merging more often and/or in
> inplace compress.  For your specific application would it work if 
> inplace compress got table level locks during the purge phase?
> 

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