Hi, I'm aware that the MVStore currently uses a lot more disk space than the PageStore. I expect big improvements in this area in the next months. I think in the future, disk space usage will be about the same. It will probably use a bit more disk space temporarily, but if you keep the database open then the file will shrink automatically to about the same size as with the PageStore.
> It took approx 30 minutes for the db lock file to clean-up How did you stop or close the database? Did you run "shutdown defrag" or so? Could you take a few (30 or so) full thread dumps during the shutdown? To do that, use "jps -l" to get the process id, then "jstack -l <pid> >> threadDumps.txt" to get the thread dumps. > The MSGDATE field is part of the primary key You did not answer this question. 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. Regards, Thomas On Fri, Jul 18, 2014 at 4:44 PM, Kenton Garner <[email protected]> wrote: > 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. >>>> >>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "H2 Database" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to [email protected]. >>>> To post to this group, send email to [email protected]. >>>> Visit this group at http://groups.google.com/group/h2-database. >>>> For more options, visit https://groups.google.com/d/optout. >>>> >>> >>> -- > You received this message because you are subscribed to the Google Groups > "H2 Database" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/h2-database. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "H2 Database" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/h2-database. For more options, visit https://groups.google.com/d/optout.
