Hi, The PageStore is a classical storage system with redo and undo log, and overwrites old data (in a save way). The MVStore doesn't overwrite data immediately, but wait doing that for at least 1 minute. In theory, the PageStore needs less (measurable) disk space, but in practise, with solid state disks, the internal disk space usage is not actually all that different.
But I understand the MVStore disk space usage still needs to be improved, that's also a reason why the 1.4 branch is not marked as stable. However it was improved since version 1.4.185 until now. So I suggest to use the latest version of H2 and try again. Also with "shutdown defrag". Regards, Thomas On Wednesday, July 20, 2016, ck <croc...@gmail.com> wrote: > Also, > do you have some performance comparison between MVSTORE and old structure? > > I admin that > 1) MVStore is actually a future-proof way to store data and it is simply > exciting to write to database using Maps (which I blindly LOVE) and > without JDBC o SQL drivers > 2) The database read/write timings are efficient and fast (But I can't say > if it actually faster than before, as it was anyway always performant) > > The db is anyway in production and quite new, and it simply can't be 10x > or more bigger than normal. in 1 year it will be several gigs going this > way and this is simply not possible because it will cause problems in the > long run and 'sometimes' indefinitely in the future > > I think I will immediately jump to the MVS train when it is most stable > and secure, so please when it will, you should state it in big words in h2 > website as many could be interested > > Thank you > > > Il giorno martedì 19 luglio 2016 05:36:05 UTC+2, ck ha scritto: >> >> This is my first post on this group, >> Hello to everyone! :) >> >> I have a problem with my H2 DATABASE. >> I am seriously worried by the size it is getting, it is now about 350mb >> (Yeah I know it's not the largest one), but my worries go all to the future >> and how it will scale in the long run. >> >> Issues: >> - Trying to Export data as CSV using DataGrip (or any other Database >> Explorer) I get less than 50mb of real 'data' >> - Database seems filled with tons of 'unknown' data - I know the database >> stores indexes and such, but I tried DROPPING ALL OBJECTS, or DELETING >> TABLES , DELETING INFORMATION_SCHEMA just for test purpose and after all >> was cleaned it was around 250mb anyway. >> - After cleaning the whole DB which is now totally empty but still >> weights 250mb, the size changes after connect/disconnect, lowering abour >> 4mb each time >> - Deleting tables o creating tables and adding 1000 rows does not change >> file size (?) - and many times dropping tables/rows does not lower the DB >> Size (why?) >> - After cleaning the whole DB which is now totally empty, still weights >> 250mb, what is happening? >> >> >> Details: >> - I have INCREMENTAL IDS (with some jumping sequences, eg. from 10->40) >> - I store BLOBs >> - I store VARCHARs, many fixed to 125 chars, some with 250/500 or 2000 in >> a unique case >> - I use a JVM Web App that starts connection at program start and closes >> it at program closing (I used this approach because I thought it could be >> very slow and could waste tons of resources to 'reopen, commit, close' >> connection every single time, considering multiple people send multiple >> requests simultaneously. I am free too critics and I totally encourage >> opinions/advices about this. >> - Every query is immediately turned to a Map of results and the ResultSet >> is closed as soon as possible >> >> >> What is happening? I am mostly concerned about the fact it may get such a >> large db in production to cause slowdowns or crashes of the machine >> >> Might my question have some mistakes, feel free to correct me and >> apologize for my first post >> > -- > 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 h2-database+unsubscr...@googlegroups.com > <javascript:_e(%7B%7D,'cvml','h2-database%2bunsubscr...@googlegroups.com');> > . > To post to this group, send email to h2-database@googlegroups.com > <javascript:_e(%7B%7D,'cvml','h2-database@googlegroups.com');>. > Visit this group at https://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 h2-database+unsubscr...@googlegroups.com. To post to this group, send email to h2-database@googlegroups.com. Visit this group at https://groups.google.com/group/h2-database. For more options, visit https://groups.google.com/d/optout.
