2009/12/7 sam pio <hiiiiiii...@gmail.com>: > Hi all, > we have an application which uses H2 as an embedded > database.In that application we constantlly write into the db > synchronizing. and we also query and update simultaneously. I find > that the overall operation of my program is 4 times slower in the unix > environment(Sun Solaris 5.10) compared to my local PC(Windows XP). > I use the same source code, same h2.jar, same input data. but i find > when i start the two program at the same time, in XP it takes only 15 > min. but in unix it takes 1 hr. This is really bad. > my local pc is dual core whereas the unix environment has 16 > processors. which means unix has to be 8 times more faster.. but the > scenario is reverse.. > I doubt on the H2.jar for the performance...does to h2 jar behaves > like this. Has anyone seen such performance.. > What way can we increase the performance of the whole jar..
Unless you can assert that you application is CPU bound, a gajillion processors wont speed up you app by a single millisecond. Almost everything I've seen with H2 is purely IO bound. So what you are seeing is slow IO on the Solaris box. This can have several reasons: bad raid setups, slow disks, networked file systems, bad choice of filesystem, other processes hogging the IO time etc. I have not tested it, but I would be much surprised if H2 was slow on a Solaris installation with local disks and no other processes competing for IO. So check if you app is on 100% CPU usage in 'top', if that is the case multi threading will help. However; I am almost willing to bet that you see its CPU usage around 10% - unless you have other code in your app hogging up CPU cycles. In this case you have an IO problem and you need to solve that. -- Cheers, Mikkel -- You received this message because you are subscribed to the Google Groups "H2 Database" group. To post to this group, send email to h2-datab...@googlegroups.com. To unsubscribe from this group, send email to h2-database+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/h2-database?hl=en.
