Some things to look at: (1) Is this reproducable when running on a local drive? (2) turn on -verbosegc and see if the pauses are related to GC events
Navjot Singh wrote: > Hi, > > I tried setting up WRITE_DELAY to 30000 but I still get those slow > inserts approx every 500ms. > > Is there something I am missing completely? > > regards > Navjot Singh > > On Sep 6, 5:44 pm, Noel Grandin <[email protected]> wrote: >> See here:http://h2database.com/html/advanced.html >> the discussion on durability. >> >> WRITE_DELAY sets the delay between writes being committed to disk. >> >> You could set it to longer, and you will gain more performance on >> average, but risk losing more data if you have a power failure. >> >> >> >> On Tue, Sep 6, 2011 at 16:10, Navjot Singh <[email protected]> wrote: >>> Hi, >>> Can anyone explain a bit more about this option - what it exactly >>> achieves? >>> SET WRITE_DELAY >>> regards >>> Navjot Singh >>> On Sep 6, 9:51 am, Navjot Singh <[email protected]> wrote: >>>> Hi, >>>> I read some posts on the 'slow insert performance' reported by others >>>> but couldnt seem to figure out an approach to improve on this. Just >>>> wanted to share my problem and pick some brains about how others >>>> solved their problem and may offer some tips. >>>> In my use case, there is a ever running process which does some >>>> analytics and keep generating the output data. This output data we >>>> save in H2 (version 1.3.157). We are using mixed mode as we got 2 >>>> processes writing to same database. >>>> The database file is lying on the shared network drive but fast r/w >>>> otherwise. Cache is 64MB. We use connection pool and a db close delay >>>> of 5s and rest all is default. >>>> I have noticed that upto ~80k rows, the insert perf is fast, hardly >>>> touches a ms but then gradually becomes slow. After that, >>>> approximately every 5th insert operation (or one about every half a >>>> sec) seems to be taking on an avg of 300ms while others keep inserting >>>> in about a 1 ms or less time. So with my shallow knowledge of H2, it >>>> seems that inserts shall be okay, there is something else happening >>>> within H2 at regular interval which is causing this extra time. >>>> What could be the possible cause? Please help me understand this. Is >>>> there some file operation that H2 is doing which can cause them to be >>>> slow as I read about some sync() being slow. >>>> I have profiled our application which doesnt seem to be contributing >>>> to this behavior. >>>> regards >>>> Navjot Singh >>> -- >>> You received this message because you are subscribed to the Google Groups >>> "H2 Database" group. >>> To post to this group, send email to [email protected]. >>> To unsubscribe from this group, send email to >>> [email protected]. >>> For more options, visit this group >>> athttp://groups.google.com/group/h2-database?hl=en.- Hide quoted text - >> - Show quoted text - -- You received this message because you are subscribed to the Google Groups "H2 Database" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/h2-database?hl=en.
