Where I work, we are in need of upgrading our ClearCase servers and it's been proposed that we move them into a new (yet-to-be-deployed) VMmare system.
In the past I've not noticed a significant problem with performance with most applications when running in VMs, but given that ClearCase "speed" (i.e. dynamic-view response times) is so latency sensitive I am concerned that this will not be a good idea.
VMWare has numerous white-papers detailing performance related issues based on network traffic patterns that re-inforces my hypothesis, but nothing particularly concrete for this particular use case that I can see.
What I can find are various forum posts online, but which are somewhat dated, e.g.:
ClearCase clients are supported on
VMWare, but not for performance
issues. I would never put a production
server on VM. It will work but will be
slower. The more complex the slower it
gets. accessing or building from a
local snapshot view will be the
fastest, building in a remote VM
stored dynamic view using clearmake
will be painful..... VMWare is best
used for test environments
(via http://www.cmcrossroads.com/forums?func=view&catid=31&id=44094&limit=10&start=10)
and:
VMware + ClearCase = works but
SLUGGISH!!!!!! (windows)(not for
production environment) My company
tried to mandate that all new apps or
app upgrades needed to be on/moved
VMware instances. The VMware instance
could not handle the demands of
ClearCase. (come to find out that I
was sharing a box with a database
server)
Will you know what else would be on
that box besides ClearCase?
Karl
(via http://www.cmcrossroads.com/forums?func=view&id=44094&catid=31)
and:
... are still finding we can't get the
performance using dynamic views to
below 2.5 times that of a physical
machine. Interestingly, speaking to a
few people with much VMWare experience
and indeed from running builds, we are
finding that typically, VMWare doesn't
take that much longer for most
applications and about 10-20% longer
has been quoted.
(via http://www.cmcrossroads.com/forums?func=view&catid=31&id=44094&limit=10&start=10)
Which brings me to the more direct question: Does anyone have any more recent experience with ClearCase servers on VMware (if not any specific, relevant performance advice)?