What would be the JDBC url for such nio in-memory node? Could not find a way to make it work...
On Monday, October 19, 2015 at 8:40:58 PM UTC+2, Noel Grandin wrote: > > You might want to try the "nio" in-memory mode, it's likely to be more > space efficient and easier on the GC, since it stores data off the GC heap. > On Mon, 19 Oct 2015 at 18:43, Csaba Sarkadi <[email protected] > <javascript:>> wrote: > >> Hi, >> >> It is not really a question, rather an experience summary with H2 (we are >> using H2 1.4.190). >> >> We had a business need for a huge memory cache (talking about 110M >> records), for a faster query option in our statistical queries. >> Finally, we have decided to use H2 instead of caching (with this option >> we have to modify less existing code, so we can go towards with our >> existing JDBC Pooling handlers). >> >> So basically, the cached records are simple ones with 1 long and 6 >> integer columns (so 32 bytes for each record). >> Not talking about the load time (in a simple server, the copy from the >> existing MS SQL db is about 2-4 hours, depending on the current load), here >> are our results: >> >> 1. 110M records in a in memory H2 db is about 35-36GBs of memory >> 2. Simple queries are extremely fast (thanks Thomas!) >> 1. like select count(*) is 1ms >> 2. selecting records and counting them by integer ranges are a >> maximum of 35 seconds (without indexes wow - it is not really faster >> with >> indexes on a normal SQL Server) >> 3. Due to the storage mechanics, memory usage is not linear with the >> record count >> 1. like 10M records was about 9GBs of memory >> 2. 25M records were about 21GBs of memory >> 3. 110M records were 35-36GBs of memory >> 4. HASH index creation (after the table was filled) killed the server >> 1. => create the hash index before populating the server >> >> >> Hope I could help everyone with these data (If I have anymore to add, I >> will). >> Also, if it is possible, we would like to make some personal contact with >> Thomas (couldn't find your mail, just this mailing list) - so both of us >> could learn from handling bigger inmemory DBs :) >> >> >> Thanks, >> >> Csaba Sarkadi >> >> >> >> >> -- >> 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] <javascript:>. >> To post to this group, send email to [email protected] >> <javascript:>. >> 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.
