Re: How much memory(RAM) required for OS running Oracle

On Jul 5, 7:42 am, harvinde...@xxxxxxxxx wrote:
Hi,

We are setting up couple of boxes on Linux with different hardware
specs and trying to prepare a document that can be used as general
guidelines for future installations.
In SQL Server installations, for system with <16GB we allocate 1GB for
OS and rest of memory for Database and for system with >16GB we
allocate 2GB for OS and rest of memory for database.
So we are wondering how much memory is required by OS(Linux) for
Oracle installation and allocate remaining memory for Database (SGA +
PGA etc).
Also By default Oracle recommends 40% of RAM for SGA but that may be
good for small system but may not be applicable for large system. It
is also true that we can't have a generic set
of recommendations since it also depends upon the application and
other factors etc but still it will be good to have some starting
point (not 40%) so that DBA can configure the system and then modify
the settings as required. It may be possible that such type of
document already exists and it will be great if can point me to
location or send me your feedback about what can SGA+PGA are set for
particular RAM on machine, so document will look like:

RAM (GB) DB_CACHE_SIZE
SHARED_POOL_SIZE PGA_AGGREGATE_TARGET
LARGE_POOL_AREA JAVA_POOL_SIZE etc

2
4
8
12
16
32
64

Environment: Oracle 10.2.0.3 on RHAT4

Thanks
--Harvinder

You can't really be that generic because of the wide variation of
applications, options and configurations. If you know ahead of time a
limited number of applications and configurations, maybe you can
empirically determine these things for your organization. But if you
are going to have a data warehouse, a third-party app, XE and custom
shared-server in your organization, for example, each will have widely
varying requirements based not least on number of users.

Metalink has some docs on how to figure out unix memory usage and
such, poke around there. There are a few how-to-configure
methodologies floating around (IIRC a google for Shallahammer might
find something), but really, you need a DBA to empirically test for
details once you have something up and running. The more recent
versions of Oracle can work with the defaults at least to get started,
some DBA's might have rules of thumb for buffers and optimization
parameters for particular types of workloads. Most large applications
like ERP or MRP have some recommendations.

I think some docs about PGA settings may be misleading (or at least
only applicable to narrow configurations that are not specified
clearly).

jg
--
@home.com is bogus.
"New size for Men especially for new feelings of women at once!" -
Spam

.

Relevant Pages

  • Re: ORA-04031 with Collections and SGA Settings - Part II
    ... Are these settings normal or is there something off in them that would ... What 'cache hit ratio' is being displayed? ... Other memory: probably the log_buffer of 54 Mb???? ... However decided to set those values doesn't have a clue about Oracle, ...
    (comp.databases.oracle.server)
  • Re: Perf Issue - Wait IO is High
    ... > memory pages stays down around the low threshhold of 120 pages, ... > Oracle datafile pages), and it is constantly reading new ones in. ... > memory pages with vmtune, but since that is what the app needs most ... If you say that the vmtune settings are default, ...
    (comp.unix.aix)
  • Re: how to configure SQL Server 7.x memory
    ... in sybase) to fix a set amt of memory if it is less than 4 ... >other applications. ... >So, if it is a dedicated SQL server, leave it alone. ... >> SQL server memory settings please? ...
    (microsoft.public.sqlserver.server)
  • Re: xmalloc string functions
    ... require memory allocations depending on the way the system works. ... If the toolkit being used is not one of those, then it is irrelevant that some provide a means to do so, particularly if the "some" are not available for the platform being targeted. ... Not enough context for most real-world applications to recover at this point. ... At this point g_malloccalling abortbecomes a moot point, particularly if your auto-save code is robust against memory allocation errors. ...
    (comp.lang.c)
  • Re: ProDOS Plus
    ... operating system was not considered worth the problems when it was just as easy to make the applications support 128k or more ram. ... your suggested P-code system could do something similar by running in the aux 64k memory range $D000...FFFF or perhaps the aux ram used by the P8 /ram driver code space. ... the OS could fit in *only* the space that ProDOS now occupies. ... if practicality were a concern we probably wouldn't be using old hardware. ...
    (comp.sys.apple2)