RE: Loading small tables into memory for the application lifetime

From: Scott Anderson (sanderso..irvana.com)
Date: Mon Jun 30 2008 - 09:42:23 EDT

  • Next message: Michael Gentry: "Re: Loading small tables into memory for the application lifetime"

    Within a given context, unique database rows exist as unique objects. You could cache these objects with strong references, which would prevent them from being GC'd.

    -----Original Message-----
    From: oyvindharbo..mail.com [mailto:oyvindharboe@gmail.com] On Behalf Of Øyvind Harboe
    Sent: Monday, June 30, 2008 9:06 AM
    To: cayenne-use..ncubator.apache.org
    Subject: Loading small tables into memory for the application lifetime

    In the apps I'm working on I can generally sort tables into two
    categories:

    1. tables that change as part of normal operation of the database
    and/or where the number of records is too large to fit into memory

    2. various and sundry small tables. These have a small number
    of records, change infrequently and can easily fit into memory. Loading
    these tables take an instant(lest I'd categorize them as #1 tables).

    #1 has relationships to #2 entries. These are constantly resolved via
    sql queries.
    At a guess I'd say that 95% of all queries are to resolve relationships from
    #1 to #2. Ideally I should be able to mark a table as #2 via a configuration
    option in my application as part of hardcoded tweaking of the app.

    Is there a way to load #2 permanently into memory so as to avoid
    SQL statements to resolve relationships from #1 to #2?

    Since loading all #2 tables take an instant, they could be dumped if
    more than N seconds has passed since they were last used.

    -- 
    Øyvind Harboe
    http://www.zylin.com/zy1000.html
    ARM7 ARM9 XScale Cortex
    JTAG debugger and flash programmer
    



    This archive was generated by hypermail 2.0.0 : Mon Jun 30 2008 - 09:42:56 EDT