Informix on Linux on VMWare

[Keith Simmons]

Hi

It looks like I am going to have to migrate an IDS instance from Solaris to
Linux.
Current machine is a 16Gb dual chip SPARC T5120 with twin path, fibre
attached disk (Raid 1) running IDS 11.5 on Solaris 5.10.
Target machine is likely to be similar memory on a generic Intel platform
with what-ever disk the hosting company provides :-( This will run VMWare v
4 or 5 and have Linux running in a VM and IDS latest.
Machine is only used as a transient area (currently) acting as the target
for ER and a source for CDC onward to $Q1$erver.
Any thoughts to help me along the way would be appreciated such as the
'best' Linux distro to use, number/speed of processors required.
Data migration will not be an issue as I will build from scratch using
extracts/loads from the ER Source to re-instantiate ER.

Many Thanks

Keith

[Art Kagel]

Keith:

Points:

- All Linux distros are about the same to my mind. I've used RH, Ubuntu
(Debian based), and SUSE and all work just fine with Informix.
- Any Intel processor you select and any number of cores will outperform
the T-class Niagra CPU cores in the Sun T5120 which was actually engineered
to run web servers and highly threaded Java applications well and so runs
all of the major databases poorly (Sybase comes closest to being able to
run acceptably on these chips). Informix's thread library is proprietary
and does not use OS threads so the chip sees each of the oninit processes
as a massive single thread which it cannot run well because the Niagra chip
has no read-ahead or multi-branch pre-fetch features. Oracle/Sun is trying
to reengineer this chip class so Oracle can run decently on them - so far
no announcements.
- IO performance under VMWare hosted OSes is VERY VERY POOR. If you use
vSphere it's significantly better than without that hypervisor, but still
far behind running on bare silicone. If your IO requirements are very
modest, you may be OK. I wouldn't try to run a major retail outlet or
other high transaction rate OLTP installation under VMWare, however.
- Consider upgrading from 11.50 to 11.70.FC7 or later during the
migration. New features, a bit more speed, and 11.50 won't be supported
for too much longer once version 12 is released in the spring, so why take
the upgrade hit again in a year or two.

Art
Art S. Kagel
Advanced DataTools (www.advancedatatools.com)
Blog: http://informix-myview.blogspot.com/

Disclaimer: Please keep in mind that my own opinions are my own opinions
and do not reflect on my employer, Advanced DataTools, the IIUG, nor any
other organization with which I am associated either explicitly,
implicitly, or by inference. Neither do those opinions reflect those of
other individuals affiliated with any entity with which I am affiliated nor
those of the entities themselves.

Post by Keith Simmons
Hi
It looks like I am going to have to migrate an IDS instance from Solaris
to Linux.
Current machine is a 16Gb dual chip SPARC T5120 with twin path, fibre
attached disk (Raid 1) running IDS 11.5 on Solaris 5.10.
Target machine is likely to be similar memory on a generic Intel platform
with what-ever disk the hosting company provides :-( This will run VMWare v
4 or 5 and have Linux running in a VM and IDS latest.
Machine is only used as a transient area (currently) acting as the target
for ER and a source for CDC onward to $Q1$erver.
Any thoughts to help me along the way would be appreciated such as the
'best' Linux distro to use, number/speed of processors required.
Data migration will not be an issue as I will build from scratch using
extracts/loads from the ER Source to re-instantiate ER.
Many Thanks
Keith
_______________________________________________
Informix-list mailing list
http://www.iiug.org/mailman/listinfo/informix-list

[Nick Lello]

From (bad) experience; get as much memory as possible dedicated to the VM

and use it for read-ahead buffering.

The low I/O bandwidth will really hurt you if there's any decent amount of
buffer churn / updates.

Try to persuade your VM admin to get you a virtual disk on an underused
storage path and use this for logs

Hi
It looks like I am going to have to migrate an IDS instance from Solaris
to Linux.
Current machine is a 16Gb dual chip SPARC T5120 with twin path, fibre
attached disk (Raid 1) running IDS 11.5 on Solaris 5.10.
Target machine is likely to be similar memory on a generic Intel platform
with what-ever disk the hosting company provides :-( This will run VMWare v
4 or 5 and have Linux running in a VM and IDS latest.
Machine is only used as a transient area (currently) acting as the target
for ER and a source for CDC onward to $Q1$erver.
Any thoughts to help me along the way would be appreciated such as the
'best' Linux distro to use, number/speed of processors required.
Data migration will not be an issue as I will build from scratch using
extracts/loads from the ER Source to re-instantiate ER.
Many Thanks
Keith
_______________________________________________
Informix-list mailing list
http://www.iiug.org/mailman/listinfo/informix-list

[Ian Goddard]

Post by Keith Simmons
Hi
It looks like I am going to have to migrate an IDS instance from Solaris
to Linux.
Current machine is a 16Gb dual chip SPARC T5120 with twin path, fibre
attached disk (Raid 1) running IDS 11.5 on Solaris 5.10.
Target machine is likely to be similar memory on a generic Intel
platform with what-ever disk the hosting company provides :-( This will
run VMWare v 4 or 5 and have Linux running in a VM and IDS latest.
Machine is only used as a transient area (currently) acting as the
target for ER and a source for CDC onward to $Q1$erver.
Any thoughts to help me along the way would be appreciated such as the
'best' Linux distro to use, number/speed of processors required.
Data migration will not be an issue as I will build from scratch using
extracts/loads from the ER Source to re-instantiate ER.

FWIW the Informix Virtual Appliance (
http://www.ibm.com/developerworks/wikis/display/im/ibm+virtual+appliances#IBMVirtualAppliances-ids
) seems to be based on SLES 11.