Re: Informix vs. Sybase vs. Oracle vs. (gasp) MS SQL Server

In article <861943179.18332@dejanews.com>, Brenda Muller <BMReed@aol.com> writes >In article <5j6eju$h25@omni2.voicenet.com>, > gray@voicenet.com (Scott Gray) wrote: >> >> In article <33538a45.29051694@news.jax.mindspring.com>, >> Reid Fleming <RFleming@aol.com> wrote: >> >Dave Raddatz <raddatz@austin.ibm.com> wrote: >> > >> >>Steve Phelan wrote: >> >> >> >>I think Larry's referring to the SP machines (mutltiple RS/6000 >> >>node environment) vs. what you describe as SMP machines (multiple >> >>chips in a single box). >> >> >> >>I believe several DB vendors have written "parallel" versions >> >>of their products to take advantage of the SP type machines. >> >> >> > >> >If they have, I would be interested in seeing how they turned out. We >> >had one of the first SP2's that we tried using with Sybase System 10. >> >Performance was poor; Sybase recommended that we wait until their >> >'Navigation Server' became available. We waited for a while, but the >> >product, which they were co-developing with NCR (I believe) was >> >dropped. >> >> Nope, it wasn't dropped, and is available right now. Only >> the name was changed, it is currently called Sybase MPP 11.1. >> I managed to play with it a while ago, and it is quite cool >> (although, as with *any* clustering system, is pretty hard >> to maintain). Also, Sybase's future direction with the new >> Adaptive server architecture is to roll MPP into the Server >> itself. >> > >Oracle's product is Oracle Parallel Server (OPS), and Informix's >product is Informix XPS. I only have direct experience with >OPS, which is a nightmare on MPP systems such as the SP2. My >understanding is that it is much better on clustered SMP >systems. I have heard that Informix's XPS product is really >nice, and I have a vague memory of seeing an Informix benchmark >against Oracle and Sybase benchmarks on the SP2 in which Informix >was clearly the winner. Does anyone have more information about >how this product differs from Oracle or Sybase? > >> >I'm not an internals expert, but several DB vendors in the past have >> >spoken of how much more difficult it is to 'parallelize' between >> >machines, versus between processors (like Informix, and to a lesser >> >extent, Oracle, are able to do). I like the idea of separate boxes, >> >and hope that they can make (or have made) this work. >> >> It works, but is a really hard problem (just think of the variables >> involved with optimization). Now with the hybrid NUMA approach >> I bet you'll start to see a lot of development in the direction >> of tuning databases towards a more distriubuted approeach. >> > >Database solutions for MPP are not really marketed as being >high-performing, scaleable solutions. They are marketed as Maybe not by Oracle but they are by Informix.... >solutions for high-availability. If you think about the problems >and overhead associated with say 30 servers all responsible for >one data bed, and moving data between memory on the servers, Do not move it - try to organise the data so you can do co-located joins i.e. joins on one server. >it quickly becomes clear that the administrative overhead would >have to be extremely large. Latency between memory on servers Not really. >in an MPP configuration is a real problem. Not to mention the Agreed - try to avoid. >human administrative factor - 30 operating systems and 30 copies >of database software. It's a complete nightmare. And the DBMS OS installs tends to be fairly automatic these days, just insert cd and select options and wait...At least HP was when I saw HP-UX 10 being installed.... For Informix ********************************************************* *** NOTE I HAVE NOT USED INFORMIX-XPS ONLY DSA *** *** I MAKE A SWEEPING GENERALISATION THAT THE INSTALL *** *** PROCEDURE FOR XPS IS THE SAME AS DSA 7.x *** *** (I KNOW XPS USES ONCONFIG FILES THE SAME AS DSA *** ********************************************************* You :- 1. $INFORMIXDIR to where you want it installed 2. cd $INFORMIXDIR 3. Add $INFORMIXDIR/bin to your path 4. Use tar or cpio to extract the tape. 3. Run ./installonline and enter serial key and license number 4. Setup $INFORMIXDIR/etc/$ONCONFIG (can also the the same on each machine - just edit the name of server). 5. Create $INFORMIXDIR/etc/sqlhosts with the hostname and service name in /etc/service Note this is identical on each machine 6. Setup /etc/services again indentical on each machine. 7. Add startup/shutdown commands to /etc/rc.* if you base the name of the online instance on the hostname of the machine then a shell script containing sed command and a few templates can be used to automate 4-7 by using uname to get the name of the machine ( sed 's/THESERVER`uname -n`' < template > file ). Then run oninit -i to startup the server with an initial area of d disk. Being really flash you could dd the tape into a file, rcp the tar or cpio file to each machine and use rsh to extract. Admittedly you would need to manually license each machine (unless you rcp except onto the machine and use it to drive the install program). [ Authors Note - Hmm I feel an idea for a tool forming..] ********* THIS BIT I KNOW (From Eliazabeth Suto's book 2nd edition) You then define a co-group (group of Online servers on several machine - in this case 30 servers one per machine) You can then create dbslices ( one dbslice = an area of disk which is simulatanously added to each server in the group of servers you define. E.g. /dev/rdsk/c1t0d0s0 offset 30K size 1.9Gb). This allows this area of disk to be added to Online ON EACH SERVER AUTOMATICALLY...... >needs to know at all times who has what where. > Automatically handle by XPS. >The only real performance advantage one would have with an >MPP system is the complete removal of backplane limitations. >When you can just keep adding boxes, backplane problems >disappear. So it is scaleable, in a sense. > Agreed, >The big boy hardware vendors are now all attempting to combine >SMP and MPP together in some way. So now we're seeing future Sounds the way to go - perhaps several servers grouped to form a mini-database wharehouse one per major site (country?) and XPS controlling the data access allowing global i.e. planet wide queries...!!!). >plans like clustered SMP systems with fiber between the boxes, >or some NUMA-like MPP systems with "memory" connectivity >between boxes (I still don't see how that would work). The Think of the memory bus being extended into an ethernet network between machines. If the memory is 'local' to the processor (think of memory local to machine) then that is a normal memory access. If the memory is 'remote' to the processor (think of memory on a diffent machine) then the memory request is sent across a different bus (think network packet containing the request sent acroos a network with a reply packet sent