topic Re: sharing memory in Operating System - HP-UX

sharing memory

baddou — Thu, 25 Mar 2004 14:30:01 GMT

Hello
I have two Servers Srv1 and Srv2 with cluster, only Srv1 works with database and takes users requests, and the Srv2 is a secure server (Standby mode).

I want that Srv1 programs use also the Srv2 memory , how can I do?

Any suggestion please
Tanks lot

Re: sharing memory

Geoff Wild — Thu, 25 Mar 2004 14:41:52 GMT

As far as I know - this is not possible....

One possible solution would be to split the app up - oracle on 1 server and application on the other....

Rgds...Geoff

Re: sharing memory

Sundar_7 — Thu, 25 Mar 2004 14:58:16 GMT

As far as I can reach, there is no way you can do this except by physically moving the memory from Srv1 to Srv2.

Re: sharing memory

Patrick Wallek — Thu, 25 Mar 2004 15:14:22 GMT

This is not going to work. YOu can NOT use resrouces from one machine on another machine.

The only way you MIGHT get something equivalent is with Oracle Parallel server and Oracle RAC but I don't know that for sure.

Otherwise the only way to share the resources is to remove them from Srv2 and put them in Srv1.

Re: sharing memory

Sundar_7 — Thu, 25 Mar 2004 15:16:27 GMT

I dont think this is a practical suggestion. But the application can use RPC and get part of work done in Srv2.

Re: sharing memory

Steven E. Protter — Thu, 25 Mar 2004 15:25:27 GMT

I suppose you could build a service guard cluster out of these two machines. Then the load of resource use would be spread across the two machines. Effectively memory would be shared across the two machines.

Service Guard is expensive and complex. I have a class in it later next month. I'll get ya know.

If there is actually a valid performance issue Oracle does reccomend splitting the application server and the database server in many circumstances.

SEP

Re: sharing memory

baddou — Thu, 25 Mar 2004 15:26:31 GMT

Hi

What about executing a part of program on Srv1 and 2nd Part on Srv2 (Using Sub process), any idea

(I read some where that we can give some arguments to Programs in order to execute it on two servers, Time=Time/2 if same capacity of servers)

Re: sharing memory

Patrick Wallek — Thu, 25 Mar 2004 15:31:40 GMT

Service Guard does NOT share resources between boxes. Service guard provides the mechanism for failover from one box to the other.

If there is any resource sharing between boxes, or part of the application running on one machine and part on the other it would have to be done at the application level.

Re: sharing memory

A. Clay Stephenson — Thu, 25 Mar 2004 15:39:46 GMT

Well, if you had a transporter I suppose Scotty could beam the DIMM's from one box to the other but otherwise this can't be done. The closest suggestion was RPC to better share the load.

Before any meaningful suggestions can be made, you really have to identify where your current bottlenecks are. You might spend tons of money on upgrades when the real solution was a little software tweaking.

Re: sharing memory

Hein van den Heuvel — Thu, 25 Mar 2004 17:09:58 GMT

Hmmm, memories of True64 Unix on Alpha.

It supports the 'Memory Channel' 'Reflective Memory' adapters which you can program to 'reflect' memory from one box onto the next at about 100MB/Sec and latencies expressed in micro-seconds versus the milliseconds one sees for tratidional network connections (Infinitband and rdma/ip interfaces will fix that).

That was a powerfull interface, but development has frozen and most usage is similar to a network stack.

And more memories of OpenVMS Galaxies. A sort of Hpars with the ability yo share memory.

None of this will help you I'm afraid, but it does show that it is not a totaly crazy question when talking phyical memory.

But I think you have to look in application space to get a practical solution. For example, if your database is a client/server style (like oracle), you could have the client 'use' memory on the other server.

Now if you are already using Oracle, you should seriously consider RAC which wll allow you to change to active/active cluster memories form active/standby with miminal, or no, application changes.

For furhter help you will have to tell us more about your DB and application.

hth,
Hein.